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• What choices do I have for a future in software development?

  - by user354892

  After graduating from college with a degree in mathematics and a minor in computer science, I took over a year to find my first programming job. I very much enjoy my work environment, but sometimes I feel like I'm not developing professionally as quickly as I am capable of. My company does mostly web programming. The project that I work on is basically a front-end for a SQL database. The entire project is (AFAIK) coded is VB.NET. I've been working on the back-end logic of the program. After some time on the job, we decided that designing web pages is not my cup of tea. It seems like the thing that I spend more time on than anything else is searching the web and SO for information about poorly documented .net and web APIs. This does not make me happy; is this normal for a programming job; I don't think it is. It really hit me the other day when i saw a question about math asked here and I didn't know the answer; I feel like my knowledge is going stale! I was previously almost hired by another company where they design graphic-intensive battle simulations for the military. I sometimes wonder what my life might be like if I had that job. I feel like my math and problem solving skills might have been a better fit at this other company. Within the wide field of software development, there are a number of directions in which to go as evidenced by the huge variety of topics discussed here on StackOverflow. I would like to feel like I'm going in the direction where I will make the most of my skills and have a satisfying career. Let me word this question as clearly as possible: given the wide breadth of the field of software development, how does it break down into sub-fields and what are the considerations for developing a software development career. I do not want to manage my career by default.

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• How do I call C++/CLI (.NET) DLLs from standard, unmanaged non-.NET applications?

  - by tronjohnson

  In the unmanaged world, I was able to write a __declspec(dllexport) or, alternatively, use a .DEF file to expose a function to be able to call a DLL. (Because of name mangling in C++ for the __stdcall, I put aliases into the .DEF file so certain applications could re-use certain exported DLL functions.) Now, I am interested in being able to expose a single entry-point function from a .NET assembly, in unmanaged-fashion, but have it enter into .NET-style functions within the DLL. Is this possible, in a simple and straight-forward fashion? What I have is a third-party program that I have extended through DLLs (plugins) that implement some complex mathematics. However, the third-party program has no means for me to visualize the calculations. I want to somehow take these pre-written math functions, compile them into a separate DLL (but using C++/CLI in .NET), but then add hooks to the functions so I can render what's going on under the hood in a .NET user control. I'm not sure how to blend the .NET stuff with the unmanaged stuff, or what to Google to accomplish this task. Specific suggestions with regard to the managed/unmanaged bridge, or alternative methods to accomplish the rendering in the manner I have described would be helpful. Thank you.

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• java.awt -- when java outputs an image to my monitor (screen), where is the file that is output to the monitor card?

  - by user1405870

  Suppose that I am drawing a set of images using java graphics objects. Suppose that I java is outputting these images to my monitor. Where is the file or files that are sent to the monitor card (the graphical representation files). How can I take this file and save it to disk, or how can I take this file and write it to an array, or how can I take these files and combine the results of their output (to the monitor) into a single file for saving? I don't want to use a screen shot feature, I want to be able to redirect (xor capture also) the output to the monitor to some sort of byte-stream. I note that monitors are much better than semaphores, when you are talking about display capabilities; I don't need a counter example. I might not be asking the correct question. It might be that I want to capture the file while it is still in User Space, before it is put into 'Device Space'. I would like to try and capture the byte stream so that I can convert it to MPEG-4 format. I either need a streaming output from the MPEG-4 converter, coming from the streaming input, or else, I need to take static images at discrete times and convert the images. What format will the output from User Space be in? What format will the Device Space output be in? Try to keep speculation to a minimum. http://docs.oracle.com/javame/config/cdc/opt-pkgs/api/jsr927/index.html I guess that Java has made a means of displaying AWT objects on a television screen. Thank you. Ryan Zoerner

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• Connecting a 2560x1440 display to a laptop?

  - by tjollans

  Having read Jeff Atwood's blog post on Korean 27" IPS LCDs, I've been wondering to what extent these are useful in a notebook + large display situation. I own a Lenovo Thinkpad Edge E320 with 2nd gen. integrated Intel graphics. According to the spec from Intel, this should support HDMI version 1.4, and, using DisplayPort, resolutions up to 2560x1600. HDMI version 1.4 supports resolutions up to 4096×2160, however, according to c't (German), the HDMI interface used with Intel chips only supports 1920x1200. The same goes for the DVI output - dual-link DVI-D, apparently, is not supported by Intel. It would appear that my laptop cannot digitally drive this kind of resolution. Now what about other laptops? According to the article in c't above, AMD's integrated graphics chips have the same limitation as Intel's. NVIDIA graphics cards, apparently, only offer resolutions up to 1900x1200 over HDMI out of the box, but it's possible, when using Linux at least, to trick the driver into enabling higher resolutions. Is this still true? What's the situation on Windows and OSX? I found no information on whether discrete AMD chips support ultra-high resolutions over HDMI. Owners of laptops with (Mini) DisplayPort / Thunderbolt won't have any issues with displays this large, but if you're planning to go for a display with dual-link DVI-D input only (like the Korean ones), you're going to need an adapter, which will set you back something like €70-€100 (since the protocols are incompatible). The big question mark in this equation is VGA: a lot of laptops have it, and I don't see any reason to think this resolution is not supported by the hardware (an oft-quoted figure appears to be 2048x1536@75Hz, so 2560x1440@60Hz should be possible, right?), but are the drivers likely to cause problems? Perhaps more critically, you'd need a VGA to dual-link DVI-D adapter that converts analog to digital signals. Do these exist? How good are they? How expensive are they? Is there a performance penalty involved? Please correct me if I'm wrong on any points. In summary, what are the requirements on a laptop to drive an external LCD at 2560x1440, in particular one that supports dual-link DVI-D only, and what tools and adapters can be used to lower the bar?

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• Start a software company offshore

  - by Mascarpone

  Hello Everybody, I own a small, very young, EU based (Italy) company, and among other things, we sell IT solutions. I have a degree in applied mathematics, and I mainly deal with user interfaces, embedded systems, automation and web applications. You can say that I'm an enlightened entrepreneur because I work only with open source software (OS, IDE, I release under BSD , ... everything is free as in freedom), I give high importance to post sales services and customer satisfaction, plus I think I'm the best boss someone could desire (LOL), as I have google in mind when I think about IT workers rights. But the most beautiful thing is that, although everybody advised us not to use open source, is that we are quite profitable!!! (for the sixth trimester in a row). Now I offshore most of the work to an Indian company. I divide the work in modules and I outsource the longer or more trivial ones. I spend a lot of time defining the specifications and I leave the hard work to them. Using productivity bonuses, a lot of prototypes and third-party audits I think that my software has reached a very good quality level. I would like to start my own software development company, in order to improve control over process and cut costs. Obviously I can't afford the cost of labor in the EU, so I thought about opening a company in Asia. What I need Is: 1) Cheap labor - I can afford to give productivity bonuses and higher than average wages and stay profitable just because labor is cheap. 2) Many talents - I need a good level of tertiary education, and a good number of graduates, so I can hire junior developers and train and teach them according to my needs and philosophies (e.g.: open source mind) 3) Good infrastructure - buildings, transport, internet, .... everything that a company might need. I thought about 3 possible candidates: 1) India - I already work with indian people, I know that they are realiable and speak a good english. Big cities are too expensive, but maybe a small city like lucknow http://en.wikipedia.org/wiki/Lucknow could suits my needs. 2) China - They say it's cheaper than India, but I everytime I worked with a chineese company the language was a big barrier. They work hard, are somewhat skilled and cheap but maybe it's a risky path. Plus I feel a little uncofortable with their lack of human rights. 3) Philippines - Same as china: cheaper than india, but maybe less educated. Where do you think it's the best place to start a software company? Any reading or book to advise? thank you very much

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• Ubuntu stopped recognizing my iPod

  - by flashnode

  Rythmbox on Ubuntu 10.10 used to recognize my 3rd gen Nano and transfer mp3s. Now I plug it in and Ubuntu doesn't pop-up that box that asks what you want to do anymore. It is only recognized if I reboot and the thing is plugged in. Here is the output to 'lsusb -v -s bus:device' Bus 001 Device 008: ID 05ac:1262 Apple, Inc. iPod Nano 3.Gen Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x05ac Apple, Inc. idProduct 0x1262 iPod Nano 3.Gen bcdDevice 0.01 iManufacturer 1 Apple Inc. iProduct 2 iPod iSerial 3 000A27001A670128 bNumConfigurations 2 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 32 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0xc0 Self Powered MaxPower 500mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 2 bInterfaceClass 8 Mass Storage bInterfaceSubClass 6 SCSI bInterfaceProtocol 80 Bulk (Zip) iInterface 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x83 EP 3 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x02 EP 2 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 149 bNumInterfaces 3 bConfigurationValue 2 iConfiguration 4 iPod USB Interface bmAttributes 0xc0 Self Powered MaxPower 500mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 1 Control Device bInterfaceProtocol 0 iInterface 0 AudioControl Interface Descriptor: bLength 9 bDescriptorType 36 bDescriptorSubtype 1 (HEADER) bcdADC 1.00 wTotalLength 30 bInCollection 1 baInterfaceNr( 0) 1 AudioControl Interface Descriptor: bLength 12 bDescriptorType 36 bDescriptorSubtype 2 (INPUT_TERMINAL) bTerminalID 1 wTerminalType 0x0201 Microphone bAssocTerminal 2 bNrChannels 2 wChannelConfig 0x0003 Left Front (L) Right Front (R) iChannelNames 0 iTerminal 0 AudioControl Interface Descriptor: bLength 9 bDescriptorType 36 bDescriptorSubtype 3 (OUTPUT_TERMINAL) bTerminalID 2 wTerminalType 0x0101 USB Streaming bAssocTerminal 1 bSourceID 1 iTerminal 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 0 bNumEndpoints 0 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 1 bAlternateSetting 1 bNumEndpoints 1 bInterfaceClass 1 Audio bInterfaceSubClass 2 Streaming bInterfaceProtocol 0 iInterface 0 AudioStreaming Interface Descriptor: bLength 7 bDescriptorType 36 bDescriptorSubtype 1 (AS_GENERAL) bTerminalLink 2 bDelay 1 frames wFormatTag 1 PCM AudioStreaming Interface Descriptor: bLength 35 bDescriptorType 36 bDescriptorSubtype 2 (FORMAT_TYPE) bFormatType 1 (FORMAT_TYPE_I) bNrChannels 2 bSubframeSize 2 bBitResolution 16 bSamFreqType 9 Discrete tSamFreq[ 0] 8000 tSamFreq[ 1] 11025 tSamFreq[ 2] 12000 tSamFreq[ 3] 16000 tSamFreq[ 4] 22050 tSamFreq[ 5] 24000 tSamFreq[ 6] 32000 tSamFreq[ 7] 44100 tSamFreq[ 8] 48000 Endpoint Descriptor: bLength 9 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 1 Transfer Type Isochronous Synch Type None Usage Type Data wMaxPacketSize 0x00c0 1x 192 bytes bInterval 4 bRefresh 0 bSynchAddress 0 AudioControl Endpoint Descriptor: bLength 7 bDescriptorType 37 bDescriptorSubtype 1 (EP_GENERAL) bmAttributes 0x01 Sampling Frequency bLockDelayUnits 0 Undefined wLockDelay 0 Undefined Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 2 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Device bInterfaceSubClass 0 No Subclass bInterfaceProtocol 0 None iInterface 0 HID Device Descriptor: bLength 9 bDescriptorType 33 bcdHID 1.01 bCountryCode 0 Not supported bNumDescriptors 1 bDescriptorType 34 Report wDescriptorLength 208 Report Descriptors: ** UNAVAILABLE ** Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x83 EP 3 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 1 Device Qualifier (for other device speed): bLength 10 bDescriptorType 6 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 bNumConfigurations 2 Device Status: 0x0000 (Bus Powered) This ubuntu forum told me to check the automount settings under /apps/nautilus/preferences/media_automount_open in gconf-editor. And I did that. Any clues?

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• The Complementary Roles of PLM and PIM

  - by Ulf Köster

  Oracle Product Value Chain Solutions (aka Enterprise PLM Solutions) are a comprehensive set of product management solutions that work together to provide Oracle customers with a broad array of capabilities to manage all aspects of product life: innovation, design, launch, and supply chain / commercialization processes beyond the capabilities and boundaries of traditional engineering-focused Product Lifecycle Management applications. They support companies with an integrated managed view across the product value chain: From Lab to Launch, From Farm to Fork, From Concept to Product to Customer, From Product Innovation to Product Design and Product Commercialization. Product Lifecycle Management (PLM) represents a broad suite of software solutions to improve product-oriented business processes and data. PLM success stories prove that PLM helps companies improve time to market, increase product-related revenue, reduce product costs, reduce internal costs and improve product quality. As a maturing suite of enterprise solutions, PLM is still evolving to realize the promise it can provide across all facets of a business and all phases of the product lifecycle. The vision for PLM includes everything from gathering early requirements for a product through multiple stages of the product lifecycle from product design, through commercialization and eventual product retirement or replacement. In discrete or process industries, PLM is typically more focused on Product Definition as items with respect to the technical view of a material or part, including specifications, bills of material and manufacturing data. With Agile PLM, this is specifically related to capabilities addressing Product Collaboration, Governance and Compliance, Product Quality Management, Product Cost Management and Engineering Collaboration. PLM today is mainly addressing key requirements in the early product lifecycle, in engineering changes or in the “innovation cycle”, and primarily adds value related to product design, development, launch and engineering change process. In short, PLM is the master for Product Definition, wherever manufacturing takes place. Product Information Management (PIM) is a product suite that has evolved in parallel to PLM. Product Information Management (PIM) can extend the value of PLM implementations by providing complementary tools and capabilities. More relevant in the area of Product Commercialization, the vision for PIM is to manage product information throughout an enterprise and supply chain to improve product-related knowledge management, information sharing and synchronization from multiple data sources. PIM success stories have shown the ability to provide multiple benefits, with particular emphasis on reducing information complexity and information management costs. Product Information in PIM is typically treated as the commercial view of a material or part, including sales and marketing information and categorization. PIM collects information from multiple manufacturing sites and multiple suppliers into its repository, but also provides integration tools to push the information back out to the other systems, serving as an active central repository with the aim to provide a holistic view on any product sold by a company (hence the name “Product Hub”). In short, PIM is the master of commercial Product Information. So PIM is quickly becoming mandatory because of its value in optimizing multichannel selling processes and relationships with customers, as you can see from the following table: Viewpoint PLM Current State PIM Key Benefits PIM adds to PLM Product Lifecycle Primarily R&D Front end Innovation Cycle Change process Primarily commercial / transactional state of lifecycle Provides a seamless information flow from design and manufacturing through the ultimate selling and servicing of products Data Primarily focused on “item” vs. “product” data Product structures Specifications Technical information Repository for all product information. Reaches out to entire enterprise and its various silos of product information and descriptions Provides a “trusted source” of accurate product information to the internal organization and trading partners Data Lifecycle Repository for all design iterations Historical information Released, current information, with version management and time stamping Provides a single location to track and audit historical product information Communication PLM release finished product to ERP PLM is the master for Product Definition Captures information from disparate sources, including in-house data stores Recognizes the reality of today’s data “mess” across information silos Provides the ability to package product information to its audience in the desired, relevant format to meet their exacting business requirements Departmental R&D Manufacturing Quality Compliance Procurement Strategic Marketing Focus on Marketing and Sales Gathering information from other Departments, multiple sites, multiple suppliers A singular enterprise solution that leverages existing information silos and data stores Supply Chain Multi-site internal collaboration Supplier collaboration Customer collaboration Works with customers, exchanges / data pools, and trading partners to provide relevant product information packaged the way the customer desires Provides ability to provide trading partners and internal customers with information in a manner they desire, continuously Tools Data Management Collaboration Innovation Management Cleansing Synchronization Hub functions Consistent, clean and complete commercial product information The goals of both PLM and PIM, put simply, are to help companies make more profit from their products. PLM and PIM solutions can be easily added as they share some of the same goals, while coming from two different perspectives: the definition of the product and the commercialization of the product. Both can serve as a form of product “system of record”, but take different approaches to delivering value. Oracle Product Value Chain solutions offer rich new strategies for executives to collectively leverage Agile PLM, Product Data Hub, together with Enterprise Data Quality for Products, and other industry leading Oracle applications to achieve further incremental value, like Oracle Innovation Management. This is unique on the market today.

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• NET Math Libraries

  - by JoshReuben

  NET Mathematical Libraries   .NET Builder for Matlab The MathWorks Inc. - http://www.mathworks.com/products/netbuilder/ MATLAB Builder NE generates MATLAB based .NET and COM components royalty-free deployment creates the components by encrypting MATLAB functions and generating either a .NET or COM wrapper around them. .NET/Link for Mathematica www.wolfram.com a product that 2-way integrates Mathematica and Microsoft's .NET platform call .NET from Mathematica - use arbitrary .NET types directly from the Mathematica language. use and control the Mathematica kernel from a .NET program. turns Mathematica into a scripting shell to leverage the computational services of Mathematica. write custom front ends for Mathematica or use Mathematica as a computational engine for another program comes with full source code. Leverages MathLink - a Wolfram Research's protocol for sending data and commands back and forth between Mathematica and other programs. .NET/Link abstracts the low-level details of the MathLink C API. Extreme Optimization http://www.extremeoptimization.com/ a collection of general-purpose mathematical and statistical classes built for the.NET framework. It combines a math library, a vector and matrix library, and a statistics library in one package. download the trial of version 4.0 to try it out. Multi-core ready - Full support for Task Parallel Library features including cancellation. Broad base of algorithms covering a wide range of numerical techniques, including: linear algebra (BLAS and LAPACK routines), numerical analysis (integration and differentiation), equation solvers. Mathematics leverages parallelism using .NET 4.0's Task Parallel Library. Basic math: Complex numbers, 'special functions' like Gamma and Bessel functions, numerical differentiation. Solving equations: Solve equations in one variable, or solve systems of linear or nonlinear equations. Curve fitting: Linear and nonlinear curve fitting, cubic splines, polynomials, orthogonal polynomials. Optimization: find the minimum or maximum of a function in one or more variables, linear programming and mixed integer programming. Numerical integration: Compute integrals over finite or infinite intervals, over 2D and higher dimensional regions. Integrate systems of ordinary differential equations (ODE's). Fast Fourier Transforms: 1D and 2D FFT's using managed or fast native code (32 and 64 bit) BigInteger, BigRational, and BigFloat: Perform operations with arbitrary precision. Vector and Matrix Library Real and complex vectors and matrices. Single and double precision for elements. Structured matrix types: including triangular, symmetrical and band matrices. Sparse matrices. Matrix factorizations: LU decomposition, QR decomposition, singular value decomposition, Cholesky decomposition, eigenvalue decomposition. Portability and performance: Calculations can be done in 100% managed code, or in hand-optimized processor-specific native code (32 and 64 bit). Statistics Data manipulation: Sort and filter data, process missing values, remove outliers, etc. Supports .NET data binding. Statistical Models: Simple, multiple, nonlinear, logistic, Poisson regression. Generalized Linear Models. One and two-way ANOVA. Hypothesis Tests: 12 14 hypothesis tests, including the z-test, t-test, F-test, runs test, and more advanced tests, such as the Anderson-Darling test for normality, one and two-sample Kolmogorov-Smirnov test, and Levene's test for homogeneity of variances. Multivariate Statistics: K-means cluster analysis, hierarchical cluster analysis, principal component analysis (PCA), multivariate probability distributions. Statistical Distributions: 25 29 continuous and discrete statistical distributions, including uniform, Poisson, normal, lognormal, Weibull and Gumbel (extreme value) distributions. Random numbers: Random variates from any distribution, 4 high-quality random number generators, low discrepancy sequences, shufflers. New in version 4.0 (November, 2010) Support for .NET Framework Version 4.0 and Visual Studio 2010 TPL Parallellized – multicore ready sparse linear program solver - can solve problems with more than 1 million variables. Mixed integer linear programming using a branch and bound algorithm. special functions: hypergeometric, Riemann zeta, elliptic integrals, Frensel functions, Dawson's integral. Full set of window functions for FFT's. Product  Price Update subscription Single Developer License $999  $399  Team License (3 developers) $1999  $799  Department License (8 developers) $3999  $1599  Site License (Unlimited developers in one physical location) $7999  $3199    NMath http://www.centerspace.net .NET math and statistics libraries matrix and vector classes random number generators Fast Fourier Transforms (FFTs) numerical integration linear programming linear regression curve and surface fitting optimization hypothesis tests analysis of variance (ANOVA) probability distributions principal component analysis cluster analysis built on the Intel Math Kernel Library (MKL), which contains highly-optimized, extensively-threaded versions of BLAS (Basic Linear Algebra Subroutines) and LAPACK (Linear Algebra PACKage). Product  Price Update subscription Single Developer License $1295 $388 Team License (5 developers) $5180 $1554   DotNumerics http://www.dotnumerics.com/NumericalLibraries/Default.aspx free DotNumerics is a website dedicated to numerical computing for .NET that includes a C# Numerical Library for .NET containing algorithms for Linear Algebra, Differential Equations and Optimization problems. The Linear Algebra library includes CSLapack, CSBlas and CSEispack, ports from Fortran to C# of LAPACK, BLAS and EISPACK, respectively. Linear Algebra (CSLapack, CSBlas and CSEispack). Systems of linear equations, eigenvalue problems, least-squares solutions of linear systems and singular value problems. Differential Equations. Initial-value problem for nonstiff and stiff ordinary differential equations ODEs (explicit Runge-Kutta, implicit Runge-Kutta, Gear's BDF and Adams-Moulton). Optimization. Unconstrained and bounded constrained optimization of multivariate functions (L-BFGS-B, Truncated Newton and Simplex methods).   Math.NET Numerics http://numerics.mathdotnet.com/ free an open source numerical library - includes special functions, linear algebra, probability models, random numbers, interpolation, integral transforms. A merger of dnAnalytics with Math.NET Iridium in addition to a purely managed implementation will also support native hardware optimization. constants & special functions complex type support real and complex, dense and sparse linear algebra (with LU, QR, eigenvalues, ... decompositions) non-uniform probability distributions, multivariate distributions, sample generation alternative uniform random number generators descriptive statistics, including order statistics various interpolation methods, including barycentric approaches and splines numerical function integration (quadrature) routines integral transforms, like fourier transform (FFT) with arbitrary lengths support, and hartley spectral-space aware sequence manipulation (signal processing) combinatorics, polynomials, quaternions, basic number theory. parallelized where appropriate, to leverage multi-core and multi-processor systems fully managed or (if available) using native libraries (Intel MKL, ACMS, CUDA, FFTW) provides a native facade for F# developers

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• Data Mining Resources

  - by Dejan Sarka

  There are many different types of analyses, each one with its own pros and cons. Relational reports have a predefined structure, and end users cannot change it. They are simple to use for end users. Reports can use real-time data and snapshots of data to show the state of a report at specific points in time. One of the drawbacks is that report authoring is limited to IT pros and advanced users. Any kind of dynamic restructuring is very limited. If real-time data is used for a report, the report has a negative impact on the performance of the source system. Processing of the reports might be slow because the data comes from relational database management systems, which are not optimized for reporting only. If you create a semantic model of your data, your end users can create ad-hoc report structures. However, the development is more complex because a developer is needed to create these semantic models. For OLAP, you typically use specialized database management systems. You get lightning speed of analyses. End users can use rich and thin clients to interactively change the structure of the report. Typically, they do it graphically. However, the development of an OLAP system is many times quite complex. It involves the preparation and maintenance of an enterprise data warehouse and OLAP cubes. In order to exploit the possibility of real-time restructuring of reports, the users must be both active and educated. The data is usually stale, as it is loaded into data warehouses and OLAP cubes with a scheduled process. With data mining, a structure is not selected in advance; it searches for the structure. As a result, data mining can give you the most valuable results because you can discover patterns you did not expect. A data mining model structure is limited only by the attributes that you use to train the model. One of the drawbacks is that a lot of knowledge is needed for a successful data mining project. End users have to understand the results. Subject matter experts and IT professionals need to understand business problem thoroughly. The development might be sometimes even more complex than the development of OLAP cubes. Each type of analysis has its own place in an enterprise system. SQL Server has tools for all kinds of analyses. However, data mining is the most advanced way of analyzing the data; this is the “I” in BI. In order to get the most out of it, you need to learn quite a lot. In this blog post, I am gathering together resources for learning, including forthcoming events. Books Multiple authors: SQL Server MVP Deep Dives – I wrote an introductory data mining chapter there. Erik Veerman, Teo Lachev and Dejan Sarka: MCTS Self-Paced Training Kit (Exam 70-448): Microsoft SQL Server 2008 - Business Intelligence Development and Maintenance – you can find a good overview of a complete BI solution, including data mining, in this book. Jamie MacLennan, ZhaoHui Tang, and Bogdan Crivat: Data Mining with Microsoft SQL Server 2008 – can’t miss this book if you want to mine your data with SQL Server tools. Michael Berry, Gordon Linoff: Mastering Data Mining: The Art and Science of Customer Relationship Management – data mining from both, business and technical perspective. Dorian Pyle: Data Preparation for Data Mining – an in-depth book about data preparation. Thomas and Ronald Wonnacott: Introductory Statistics – if you thought that you could get away without statistics, then you are not serious about data mining. Jiawei Han and Micheline Kamber: Data Mining Concepts and Techniques – in-depth explanation of the most popular data mining algorithms. Michael Berry and Gordon Linoff: Data Mining Techniques – another book that explains data mining algorithms, more fro a business perspective. Paolo Guidici: Applied Data Mining – very mathematical book, only if you enjoy statistics and mathematics in general. Forthcoming presentations I am presenting two data mining related sessions during the PASS Summit in Charlotte, NC: Wednesday, October 16th, 2013 - Fraud Detection: Notes from the Field – I am showing how to use data mining for a specific business problem. The presentation is based on real-life projects. Friday, October 18th: Excel 2013 Advanced Analytics – I am focusing on Excel Data Mining Add-ins, and how to use them together with Power Pivot and other add-ins. This is the most you can get out of Excel. Sinergija 2013, Belgrade, Serbia Tuesday, October 22nd: Excel 2013 Analytics to the Max – another presentation focusing on the most advanced analytics you can get in Excel. SQL Rally Amsterdam, Netherlands Thursday, November 7th: Advanced Analytics in Excel 2013 – and again I am presenting about data mining in Excel. Why three different titles for the same presentation? I don’t know, I guess I forgot the name I proposed every time right after I sent the proposal. Courses Data Mining with SQL Server 2012 – I wrote a 3-day course for SolidQ. If you are interested in this course, which I could also deliver in a shorter seminar way, you can contact your closes SolidQ subsidiary, or, of course, me directly on addresses [email protected] or [email protected]. This course could also complement the existing courseware portfolio of training providers, which are welcome to contact me as well. OK, now you know: no more excuses, start learning data mining, get the most out of your data

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• Advice on learning programming languages and math.

  - by Joris Ooms

  I feel like I'm getting stuck lately when it comes to learning about programming-related things; I thought I'd ask a question here and write it all down in the hope to get some pointers/advice from people. Perhaps writing it down helps me put things in perspective for myself aswell. I study Interactive Multimedia Design. This course is based on two things: graphic design on one hand, and web development on the other hand. I have quite a decent knowledge of web-related languages (the usual HTML/JS/PHP) and I'll be getting a course on ASP.NET next year. In my free time, I have learnt how to work with CodeIgniter, aswell as some diving into Ruby (and Rails) and basic iOS programming. In my first year of college I also did a class on Java (19/20 on the end result). This grade doesn't really mean anything though; I have the basics of OOP down but Java-wise, we learnt next to nothing. Considering the time I have been programming in, for example, PHP.. I can't say I'm bad at it. I'm definitely not good or great at it, but I'm decent. My teachers tell me I have the programming thing down. They just tell me I should keep on learning. So that's what I do, and I try to take in as much as possible; however, sometimes I'm unsure where to start and I have this tendency to always doubt myself. Now, for the 'question'. I want to get into iOS programming. I know iOS programming boils down to programming in Cocoa Touch and Objective-C. I also know Obj-C is a superset of C. I have done a class on C a couple of years ago, but I failed miserably. I got stuck at pointers and never really understood them.. Until like a month ago. I suddenly 'got' it. I have been working through a book on Objective-C for a week or so now, and I understand the basics (I'm at like.. chapter 6 or so). However, I keep running into similar problems as the ones I had when I did the C class: I suck at math. No, really. I come from a Latin-Modern Languages background in high school and I had nearly no math classes back then. I wanted to study Computer Science, but I failed there because of the miserable state of my mathematics knowledge. I can't explain why I'm suddenly talking about math here though, because it isn't directly related to programming.. yet it is. For example, the examples in the book I'm reading now are about programming a fraction-calculator. All good, I can do the programming when I get the formulas down.. but it takes me a full day or more to actually get to that point. I also find it hard to come up with ideas for myself. I made one small iOS app the other day and it's just a button / label kind of thing. When I press the button, it generates a random number. That's really all I could come up with. Can you 'learn' that? It probably comes down to creativity, but evidently, I'm not too great at being creative. Are there any sites or resources out there that provide something like a basic list of things you can program when you're just starting out? Maybe I'm focusing on too many things at once. I want to keep my HTML/CSS at a decent level, while learning PHP and CodeIgniter, while diving into Ruby on Rails and learning Objective-C and the iOS SDK at the same time. I just want to be good at something, I guess. The problem is that I can't seem to be happy with my PHP stuff. I want more, something 'harder'; that's why I decided to pick up the iOS thing. Like I said, I have the basics down of a lot of different languages. I can program something simple in Java, in C, in Objective-C as of this week.. but it ends there. Mostly because I can't come up with ideas for more complex applications, and also because I just doubt myself: 'Oh, that's too complex, I can never do that'. And then it ends there. To conclude my rant, let me basically rephrase my questions into a 'tl;dr' part. A. I want to get into iOS programming and I have basic knowledge of C/Objective-C. However, I struggle to come up with ideas of my own and implement them and I also suck at math which is something that isn't directly related to, yet often needed while programming. What can I do? B. I have an interest in a lot of different programming languages and I can't stop reading/learning. However, I don't feel like I'm good in anything. Should I perhaps focus on just one language for a year or longer, or keep taking it all in at the same time and hope I'll finally get them all down? C. Are there any resources out there that provide basic ideas of things I can program? I'm thinking about 'simple' command-line applications here to help me while studying C/Obj-C away from the whole iPhone SDK. Like I said, the examples in my book are mainly math-based (fraction calculator) and it's kinda hard. :( Thanks a lot for reading my post. I didn't plan it to be this long but oh well. Thanks in advance for any answers.

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• Calling All Agile Customers-Share Your Stories at the Upcoming PLM Summit

  - by Terri Hiskey

  Now that we've closed the door on another Oracle OpenWorld, planning is in full swing for the next PLM Summit, taking place February 4-6, 2013 in San Francisco, in conjunction with the Oracle Value Chain Summit. This event is a must-attend for all Agile PLM customers. We will be holding five tracks with over forty Agile PLM-focused sessions covering a range of topics and industries. If you'd like to be notified once registration is live for this event, be sure to sign up at www.oracle.com/goto/vcs. CALL FOR PRESENTATIONS: We are looking for some fresh, new customer stories to share with attendees. Read below for descriptions of the five tracks, and the suggested topics that we'd like to hear from customers. If you are interested in presenting at the PLM Summit (and getting a FREE pass to attend if your presentation is accepted!) send me an email at terri.hiskey-AT-oracle.com with: Your proposed session title and the track your session fits into 3-5 bullets of takeaways that attendees will get from your presentation Your complete contact information including name, title, company, telephone number and email The deadline for this call for presentations is Thursday, November 15, so get your submission in soon! PLM Track #1:  Product Insights and Best Practices This track will provide executive attendees and line of business managers with an overview of how Agile PLM has been deployed and used at customers to enable and manage critical product-related business processes including enterprise quality and supplier management, compliance, product cost management, portfolio management, commercialization and software lifecycle management. These sessions will also provide details around how to manage the development and rollout of the solutions and how to achieve and track value. Possible session topics: Software Lifecycle Management Enterprise Quality Management New Product Development Integrated Business Planning ECO effectivity planning Rapid Commercialization             Manage the Design to Release Process for Complex Configured Products PLM for Life Sciences Companies I (Compliant Data Set) PLM for Life Sciences Companies II (eMDR, UDI) Discrete CPG – Private Label Mgmt Cost Management and Strategic Sourcing IP Mgmt in the Semiconductor Industry Implementing the Enterprise Training Record using Agile PLM PLM Track #2: Product Deep Dives & Demos This track is aimed at line of business  and IT managers who would like to understand the benefits of expanding their PLM footprint. The sessions in this track will provide attendees with an up-close and in-depth look Agile PLM’s newer and exciting applications, including analytics and innovation management, and will detail features and functionality that are available in the latest version of Agile PLM Possible session topics: Oracle Product Lifecycle Analytics Integrating PLM with Engineering and Supply Chain Systems Streamline PLM Design to Manufacturing Processes with AutoVue Visualization Solutions         Achieve Environmental Compliance (REACH and ROHS) with Agile Product Governance & Compliance PIM Deep Dive Achieving Integrated Change Control with Agile PLM and E-Business Suite Deploying PLM at Small and Midsize Enterprises Enhancing Oracle PQM w/APQP and 8D functionality Advanced Roles and Privileges – Enabling ITAR Model Unit Effectivity Implementing REACH with 9.3.2 Deploying Job Functions, Functional Teams in 9.3.2 to Improve Your Approval Matrix PLM Track #3: Administration & Integrations This track will provide sessions for Agile administrators, managers and daily Agile PLM users who are preparing to upgrade or looking to extend the use of their current PLM implementation through AIA and process extensions. It will include deeper conversation about Agile PLM features and best practices on managing an Agile PLM infrastructure. Possible session topics: Expand the Value of your Agile Investment with Innovative Process Extension Ideas Ensuring Implementation & Upgrade Success Ensure the Integrity and Accuracy of Product Data Across the Enterprise              Maximize the Benefits of an Integrated Architecture with AIA Integrating your PLM Implementation with ERP               Infrastructure Optimization Expanding Your PLM Implementation PLM Administrator Open Forum Q&A/Discussion FDA Validation Best Practices Best Practices for Managing a large Agile Deployment: Clustering, Load Balancing and Firewalls PLM Track #4: Agile PLM for Process This track is aimed at attendees interested in or currently using Agile PLM for Process. The sessions in this track will go over new features and functionality available in the newest version of PLM for Process and will give attendees an overview on how PLM for Process is being used to manage critical business processes such as formulation, recipe and specification management Possible session topics: PLM for Process Strategy, Roadmap and Update New Product Development and Introduction Effective Product Supplier Collaboration             Leverage Agile Formulation and Compliance to Manage Cost, Compliance, Quality, Labeling and Nutrition Menu Management Innovation Data Management Food Safety/ Introduction of P4P Quality Mgmt PLM Track #5: Agile PLM and Innovation Management This track consists of five sessions, and is for attendees interested in learning more about Oracle’s Agile Innovation Management, an exciting new addition to the Agile PLM application family that redefines the industry’s scope of product lifecycle management. Oracle’s innovation solutions enable companies to collaborate in a focused way among various functional groups (marketing, sales, operations, engineering/R&D and sourcing), combining insights of customer needs/requirements, competition, available technologies, alternate design scenarios and portfolio constraints to deliver what customers truly value. The results are better products, higher margins, greater efficiencies, more satisfied customers and the increased ability to continuously innovate. Possible session topics: Product Innovation Management Solution Overview Product Requirements & Ideation Management Concept Design Management Product Lifecycle Portfolio Management Innovation as a Competitive Differentiator

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• Yet another blog about IValueConverter

  - by codingbloke

  After my previous blog on a Generic Boolean Value Converter I thought I might as well blog up another IValueConverter implementation that I use. The Generic Boolean Value Converter effectively converters an input which only has two possible values to one of two corresponding objects.  The next logical step would be to create a similar converter that can take an input which has multiple (but finite and discrete) values to one of multiple corresponding objects.  To put it more simply a Generic Enum Value Converter. Now we already have a tool that can help us in this area, the ResourceDictionary.  A simple IValueConverter implementation around it would create a StringToObjectConverter like so:- StringToObjectConverter using System; using System.Windows; using System.Windows.Data; using System.Linq; using System.Windows.Markup; namespace SilverlightApplication1 {     [ContentProperty("Items")]     public class StringToObjectConverter : IValueConverter     {         public ResourceDictionary Items { get; set; }         public string DefaultKey { get; set; }                  public StringToObjectConverter()         {             DefaultKey = "__default__";         }         public virtual object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             if (value != null && Items.Contains(value.ToString()))                 return Items[value.ToString()];             else                 return Items[DefaultKey];         }         public virtual object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             return Items.FirstOrDefault(kvp => value.Equals(kvp.Value)).Key;         }     } } There are some things to note here.  The bulk of managing the relationship between an object instance and the related string key is handled by the Items property being an ResourceDictionary.  Also there is a catch all “__default__” key value which allows for only a subset of the possible input values to mapped to an object with the rest falling through to the default. We can then set one of these up in Xaml:-             <local:StringToObjectConverter x:Key="StatusToBrush">                 <ResourceDictionary>                     <SolidColorBrush Color="Red" x:Key="Overdue" />                     <SolidColorBrush Color="Orange" x:Key="Urgent" />                     <SolidColorBrush Color="Silver" x:Key="__default__" />                 </ResourceDictionary>             </local:StringToObjectConverter> You could well imagine that in the model being bound these key names would actually be members of an enum.  This still works due to the use of ToString in the Convert method.  Hence the only requirement for the incoming object is that it has a ToString implementation which generates a sensible string instead of simply the type name. I can’t imagine right now a scenario where this converter would be used in a TwoWay binding but there is no reason why it can’t.  I prefer to avoid leaving the ConvertBack throwing an exception if that can be be avoided.  Hence it just enumerates the KeyValuePair entries to find a value that matches and returns the key its mapped to. Ah but now my sense of balance is assaulted again.  Whilst StringToObjectConverter is quite happy to accept an enum type via the Convert method it returns a string from the ConvertBack method not the original input enum type that arrived in the Convert.  Now I could address this by complicating the ConvertBack method and examining the targetType parameter etc.  However I prefer to a different approach, deriving a new EnumToObjectConverter class instead. EnumToObjectConverter using System; namespace SilverlightApplication1 {     public class EnumToObjectConverter : StringToObjectConverter     {         public override object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             string key = Enum.GetName(value.GetType(), value);             return base.Convert(key, targetType, parameter, culture);         }         public override object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             string key = (string)base.ConvertBack(value, typeof(String), parameter, culture);             return Enum.Parse(targetType, key, false);         }     } }   This is a more belts and braces solution with specific use of Enum.GetName and Enum.Parse.  Whilst its more explicit in that the a developer has to  choose to use it, it is only really necessary when using TwoWay binding, in OneWay binding the base StringToObjectConverter would serve just as well. The observant might note that there is actually no “Generic” aspect to this solution in the end.  The use of a ResourceDictionary eliminates the need for that.

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• Is Data Science “Science”?

  - by BuckWoody

  I hold the term “science” in very high esteem. I grew up on the Space Coast in Florida, and eventually worked at the Kennedy Space Center, surrounded by very intelligent people who worked in various scientific fields. Recently a new term has entered the computing dialog – “Data Scientist”. Since it’s not a standard term, it has a lot of definitions, and in fact has been disputed as a correct term. After all, the reasoning goes, if there’s no such thing as “Data Science” then how can there be a Data Scientist? This argument has been made before, albeit with a different term – “Computer Science”. In Peter Denning’s excellent article “Is Computer Science Science” (April  2005/Vol. 48, No. 4 COMMUNICATIONS OF THE ACM) there are many points that separate “science” from “engineering” and even “art”.  I won’t repeat the content of that article here (I recommend you read it on your own) but will leverage the points he makes there. Definition of Science To ask the question “is data science ‘science’” then we need to start with a definition of terms. Various references put the definition into the same basic areas: Study of the physical world Systematic and/or disciplined study of a subject area ...and then they include the things studied, the bodies of knowledge and so on. The word itself comes from Latin, and means merely “to know” or “to study to know”. Greek divides knowledge further into “truth” (episteme), and practical use or effects (tekhne). Normally computing falls into the second realm. Definition of Data Science And now a more controversial definition: Data Science. This term is so new and perhaps so niche that the major dictionaries haven’t yet picked it up (my OED reference is older – can’t afford to pop for the online registration at present). Researching the term's general use I created an amalgam of the definitions this way: “Studying and applying mathematical and other techniques to derive information from complex data sets.” Using this definition, data science certainly seems to be science - it's learning about and studying some object or area using systematic methods. But implicit within the definition is the word “application”, which makes the process more akin to engineering or even technology than science. In fact, I find that using these techniques – and data itself – part of science, not science itself. I leave out the concept of studying data patterns or algorithms as part of this discipline. That is actually a domain I see within research, mathematics or computer science. That of course is a type of science, but does not seek for practical applications. As part of the argument against calling it “Data Science”, some point to the scientific method of creating a hypothesis, testing with controls, testing results against the hypothesis, and documenting for repeatability.  These are not steps that we often take in working with data. We normally start with a question, and fit patterns and algorithms to predict outcomes and find correlations. In this way Data Science is more akin to statistics (and in fact makes heavy use of them) in the process rather than starting with an assumption and following on with it. So, is Data Science “Science”? I’m uncertain – and I’m uncertain it matters. Even if we are facing rampant “title inflation” these days (does anyone introduce themselves as a secretary or supervisor anymore?) I can tolerate the term at least from the intent that we use data to study problems across a wide spectrum, rather than restricting it to a single domain. And I also understand those who have worked hard to achieve the very honorable title of “scientist” who have issues with those who borrow the term without asking. What do you think? Science, or not? Does it matter?

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• spoj: runlength

  - by user285825

  For RLM problem of SPOJ: This is the problem: "Run-length encoding of a number replaces a run of digits (that is, a sequence of consecutive equivalent digits) with the number of digits followed by the digit itself. For example, 44455 would become 3425 (three fours, two fives). Note that run-length encoding does not necessarily shorten the length of the data: 11 becomes 21, and 42 becomes 1412. If a number has more than nine consecutive digits of the same type, the encoding is done greedily: each run grabs as many digits as it can, so 111111111111111 is encoded as 9161. Implement an integer arithmetic calculator that takes operands and gives results in run-length format. You should support addition, subtraction, multiplication, and division. You won't have to divide by zero or deal with negative numbers. Input/Output The input will consist of several test cases, one per line. For each test case, compute the run-length mathematics expression and output the original expression and the result, as shown in the examples. The (decimal) representation of all operands and results will fit in signed 64-bit integers." These are my testcases: input: 11 + 11 988726 - 978625 12 * 41 1124 / 1112 13 * 33 15 / 16 19222317121013161815142715181017 + 10 10 + 19222317121013161815142715181017 19222317121013161815142715181017 / 19222317121013161815142715181017 19222317121013161815142715181017 / 11 11 / 19222317121013161815142715181017 19222317121013161815142715181017 / 12 12 / 19222317121013161815142715181017 19222317121013161815142715181017 / 141621161816101118141217131817191014 141621161816101118141217131817191014 / 19222317121013161815142715181017 19222317121013161815142715181017 / 141621161816101118141217131817191013 141621161816101118141217131817191013 / 19222317121013161815142715181017 19222317121013161815142715181017 * 11 11 * 19222317121013161815142715181017 19222317121013161815142715181017 * 10 10 * 19222317121013161815142715181017 19222317121013161815142715181017 - 10 19222317121013161815142715181017 - 19222317121013161815142715181017 19222317121013161815142715181017 - 141621161816101118141217131817191014 19222317121013161815142715181017 - 141621161816101118141217131817191013 141621161816101118141217131817191013 + 141621161816101118141217131817191013 141621161816101118141217131817191013 + 141621161816101118141217131817191014 141621161816101118141217131817191014 + 141621161816101118141217131817191013 141621161816101118141217131817191014 + 10 10 + 141621161816101118141217131817191013 141621161816101118141217131817191013 + 11 11 + 141621161816101118141217131817191013 141621161816101118141217131817191013 * 12 12 * 141621161816101118141217131817191013 141621161816101118141217131817191014 - 141621161816101118141217131817191014 141621161816101118141217131817191013 - 141621161816101118141217131817191013 141621161816101118141217131817191013 - 10 141621161816101118141217131817191014 - 11 141621161816101118141217131817191014 - 141621161816101118141217131817191013 141621161816101118141217131817191014 / 141621161816101118141217131817191014 141621161816101118141217131817191014 / 141621161816101118141217131817191013 141621161816101118141217131817191013 / 141621161816101118141217131817191014 141621161816101118141217131817191013 / 141621161816101118141217131817191013 141621161816101118141217131817191014 * 11 11 * 141621161816101118141217131817191014 141621161816101118141217131817191014 / 11 11 / 141621161816101118141217131817191014 10 + 10 10 + 11 10 + 15 15 + 10 11 + 10 11 + 10 10 - 10 15 - 10 10 * 10 10 * 15 15 * 10 10 / 111213 output: 11 + 11 = 12 988726 - 978625 = 919111 12 * 41 = 42 1124 / 1112 = 1112 13 * 33 = 39 15 / 16 = 10 19222317121013161815142715181017 + 10 = 19222317121013161815142715181017 10 + 19222317121013161815142715181017 = 19222317121013161815142715181017 19222317121013161815142715181017 / 19222317121013161815142715181017 = 11 19222317121013161815142715181017 / 11 = 19222317121013161815142715181017 11 / 19222317121013161815142715181017 = 10 19222317121013161815142715181017 / 12 = 141621161816101118141217131817191013 12 / 19222317121013161815142715181017 = 10 19222317121013161815142715181017 / 141621161816101118141217131817191014 = 11 141621161816101118141217131817191014 / 19222317121013161815142715181017 = 10 19222317121013161815142715181017 / 141621161816101118141217131817191013 = 12 141621161816101118141217131817191013 / 19222317121013161815142715181017 = 10 19222317121013161815142715181017 * 11 = 19222317121013161815142715181017 11 * 19222317121013161815142715181017 = 19222317121013161815142715181017 19222317121013161815142715181017 * 10 = 10 10 * 19222317121013161815142715181017 = 10 19222317121013161815142715181017 - 10 = 19222317121013161815142715181017 19222317121013161815142715181017 - 19222317121013161815142715181017 = 10 19222317121013161815142715181017 - 141621161816101118141217131817191014 = 141621161816101118141217131817191013 19222317121013161815142715181017 - 141621161816101118141217131817191013 = 141621161816101118141217131817191014 141621161816101118141217131817191013 + 141621161816101118141217131817191013 = 19222317121013161815142715181016 141621161816101118141217131817191013 + 141621161816101118141217131817191014 = 19222317121013161815142715181017 141621161816101118141217131817191014 + 141621161816101118141217131817191013 = 19222317121013161815142715181017 141621161816101118141217131817191014 + 10 = 141621161816101118141217131817191014 10 + 141621161816101118141217131817191013 = 141621161816101118141217131817191013 141621161816101118141217131817191013 + 11 = 141621161816101118141217131817191014 11 + 141621161816101118141217131817191013 = 141621161816101118141217131817191014 141621161816101118141217131817191013 * 12 = 19222317121013161815142715181016 12 * 141621161816101118141217131817191013 = 19222317121013161815142715181016 141621161816101118141217131817191014 - 141621161816101118141217131817191014 = 10 141621161816101118141217131817191013 - 141621161816101118141217131817191013 = 10 141621161816101118141217131817191013 - 10 = 141621161816101118141217131817191013 141621161816101118141217131817191014 - 11 = 141621161816101118141217131817191013 141621161816101118141217131817191014 - 141621161816101118141217131817191013 = 11 141621161816101118141217131817191014 / 141621161816101118141217131817191014 = 11 141621161816101118141217131817191014 / 141621161816101118141217131817191013 = 11 141621161816101118141217131817191013 / 141621161816101118141217131817191014 = 10 141621161816101118141217131817191013 / 141621161816101118141217131817191013 = 11 141621161816101118141217131817191014 * 11 = 141621161816101118141217131817191014 11 * 141621161816101118141217131817191014 = 141621161816101118141217131817191014 141621161816101118141217131817191014 / 11 = 141621161816101118141217131817191014 11 / 141621161816101118141217131817191014 = 10 10 + 10 = 10 10 + 11 = 11 10 + 15 = 15 15 + 10 = 15 11 + 10 = 11 11 + 10 = 11 10 - 10 = 10 15 - 10 = 15 10 * 10 = 10 10 * 15 = 10 15 * 10 = 10 10 / 111213 = 10 I am getting consistently wrong answer. I generated the above testcases trying to make them as representative as possible (boundary conditions, etc). I am not sure how to test it further. Some guidline would be really appreciated.

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• Diophantine Equation [closed]

  - by ANIL

  In mathematics, a Diophantine equation (named for Diophantus of Alexandria, a third century Greek mathematician) is a polynomial equation where the variables can only take on integer values. Although you may not realize it, you have seen Diophantine equations before: one of the most famous Diophantine equations is: X^n+Y^n=Z^n We are not certain that McDonald's knows about Diophantine equations (actually we doubt that they do), but they use them! McDonald's sells Chicken McNuggets in packages of 6, 9 or 20 McNuggets. Thus, it is possible, for example, to buy exactly 15 McNuggets (with one package of 6 and a second package of 9), but it is not possible to buy exactly 16 nuggets, since no non- negative integer combination of 6's, 9's and 20's adds up to 16. To determine if it is possible to buy exactly n McNuggets, one has to solve a Diophantine equation: find non-negative integer values of a, b, and c, such that 6a + 9b + 20c = n. Problem 1 Show that it is possible to buy exactly 50, 51, 52, 53, 54, and 55 McNuggets, by finding solutions to the Diophantine equation. You can solve this in your head, using paper and pencil, or writing a program. However you chose to solve this problem, list the combinations of 6, 9 and 20 packs of McNuggets you need to buy in order to get each of the exact amounts. Given that it is possible to buy sets of 50, 51, 52, 53, 54 or 55 McNuggets by combinations of 6, 9 and 20 packs, show that it is possible to buy 56, 57,..., 65 McNuggets. In other words, show how, given solutions for 50-55, one can derive solutions for 56-65. Problem 2 Write an iterative program that finds the largest number of McNuggets that cannot be bought in exact quantity. Your program should print the answer in the following format (where the correct number is provided in place of n): "Largest number of McNuggets that cannot be bought in exact quantity: n" Hints: Hypothesize possible instances of numbers of McNuggets that cannot be purchased exactly, starting with 1 For each possible instance, called n, a. Test if there exists non-negative integers a, b, and c, such that 6a+9b+20c = n. (This can be done by looking at all feasible combinations of a, b, and c) b. If not, n cannot be bought in exact quantity, save n When you have found six consecutive values of n that in fact pass the test of having an exact solution, the last answer that was saved (not the last value of n that had a solution) is the correct answer, since you know by the theorem that any amount larger can also be bought in exact quantity

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• Is the Scala 2.8 collections library a case of "the longest suicide note in history" ?

  - by oxbow_lakes

  First note the inflammatory subject title is a quotation made about the manifesto of a UK political party in the early 1980s. This question is subjective but it is a genuine question, I've made it CW and I'd like some opinions on the matter. Despite whatever my wife and coworkers keep telling me, I don't think I'm an idiot: I have a good degree in mathematics from the University of Oxford and I've been programming commercially for almost 12 years and in Scala for about a year (also commercially). I have just started to look at the Scala collections library re-implementation which is coming in the imminent 2.8 release. Those familiar with the library from 2.7 will notice that the library, from a usage perspective, has changed little. For example... > List("Paris", "London").map(_.length) res0: List[Int] List(5, 6) ...would work in either versions. The library is eminently useable: in fact it's fantastic. However, those previously unfamiliar with Scala and poking around to get a feel for the language now have to make sense of method signatures like: def map[B, That](f: A => B)(implicit bf: CanBuildFrom[Repr, B, That]): That For such simple functionality, this is a daunting signature and one which I find myself struggling to understand. Not that I think Scala was ever likely to be the next Java (or /C/C++/C#) - I don't believe its creators were aiming it at that market - but I think it is/was certainly feasible for Scala to become the next Ruby or Python (i.e. to gain a significant commercial user-base) Is this going to put people off coming to Scala? Is this going to give Scala a bad name in the commercial world as an academic plaything that only dedicated PhD students can understand? Are CTOs and heads of software going to get scared off? Was the library re-design a sensible idea? If you're using Scala commercially, are you worried about this? Are you planning to adopt 2.8 immediately or wait to see what happens? Steve Yegge once attacked Scala (mistakenly in my opinion) for what he saw as its overcomplicated type-system. I worry that someone is going to have a field day spreading fud with this API (similarly to how Josh Bloch scared the JCP out of adding closures to Java). Note - I should be clear that, whilst I believe that Josh Bloch was influential in the rejection of the BGGA closures proposal, I don't ascribe this to anything other than his honestly-held beliefs that the proposal represented a mistake.

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• Segmenting a double array of labels

  - by Ami

  The Problem: I have a large double array populated with various labels. Each element (cell) in the double array contains a set of labels and some elements in the double array may be empty. I need an algorithm to cluster elements in the double array into discrete segments. A segment is defined as a set of pixels that are adjacent within the double array and one label that all those pixels in the segment have in common. (Diagonal adjacency doesn't count and I'm not clustering empty cells). |-------|-------|------| | Jane | Joe | | | Jack | Jane | | |-------|-------|------| | Jane | Jane | | | | Joe | | |-------|-------|------| | | Jack | Jane | | | Joe | | |-------|-------|------| In the above arrangement of labels distributed over nine elements, the largest cluster is the “Jane” cluster occupying the four upper left cells. What I've Considered: I've considered iterating through every label of every cell in the double array and testing to see if the cell-label combination under inspection can be associated with a preexisting segment. If the element under inspection cannot be associated with a preexisting segment it becomes the first member of a new segment. If the label/cell combination can be associated with a preexisting segment it associates. Of course, to make this method reasonable I'd have to implement an elaborate hashing system. I'd have to keep track of all the cell-label combinations that stand adjacent to preexisting segments and are in the path of the incrementing indices that are iterating through the double array. This hash method would avoid having to iterate through every pixel in every preexisting segment to find an adjacency. Why I Don't Like it: As is, the above algorithm doesn't take into consideration the case where an element in the double array can be associated with two unique segments, one in the horizontal direction and one in the vertical direction. To handle these cases properly, I would need to implement a test for this specific case and then implement a method that will both associate the element under inspection with a segment and then concatenate the two adjacent identical segments. On the whole, this method and the intricate hashing system that it would require feels very inelegant. Additionally, I really only care about finding the large segments in the double array and I'm much more concerned with the speed of this algorithm than with the accuracy of the segmentation, so I'm looking for a better way. I assume there is some stochastic method for doing this that I haven't thought of. Any suggestions?

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• Inference engine to calculate matching set according to internal rules

  - by Zecrates

  I have a set of objects with attributes and a bunch of rules that, when applied to the set of objects, provides a subset of those objects. To make this easier to understand I'll provide a concrete example. My objects are persons and each has three attributes: country of origin, gender and age group (all attributes are discrete). I have a bunch of rules, like "all males from the US", which correspond with subsets of this larger set of objects. I'm looking for either an existing Java "inference engine" or something similar, which will be able to map from the rules to a subset of persons, or advice on how to go about creating my own. I have read up on rule engines, but that term seems to be exclusively used for expert systems that externalize the business rules, and usually doesn't include any advanced form of inferencing. Here are some examples of the more complex scenarios I have to deal with: I need the conjunction of rules. So when presented with both "include all males" and "exclude all US persons in the 10 - 20 age group," I'm only interested in the males outside of the US, and the males within the US that are outside the 10 - 20 age group. Rules may have different priorities (explicitly defined). So a rule saying "exclude all males" will override a rule saying "include all US males." Rules may be conflicting. So I could have both an "include all males" and an "exclude all males" in which case the priorities will have to settle the issue. Rules are symmetric. So "include all males" is equivalent to "exclude all females." Rules (or rather subsets) may have meta rules (explicitly defined) associated with them. These meta rules will have to be applied in any case that the original rule is applied, or if the subset is reached via inferencing. So if a meta rule of "exclude the US" is attached to the rule "include all males", and I provide the engine with the rule "exclude all females," it should be able to inference that the "exclude all females" subset is equivalent to the "include all males" subset and as such apply the "exclude the US" rule additionally. I can in all likelihood live without item 5, but I do need all the other properties mentioned. Both my rules and objects are stored in a database and may be updated at any stage, so I'd need to instantiate the 'inference engine' when needed and destroy it afterward.

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• Estimating the boundary of arbitrarily distributed data

  - by Dave

  I have two dimensional discrete spatial data. I would like to make an approximation of the spatial boundaries of this data so that I can produce a plot with another dataset on top of it. Ideally, this would be an ordered set of (x,y) points that matplotlib can plot with the plt.Polygon() patch. My initial attempt is very inelegant: I place a fine grid over the data, and where data is found in a cell, a square matplotlib patch is created of that cell. The resolution of the boundary thus depends on the sampling frequency of the grid. Here is an example, where the grey region are the cells containing data, black where no data exists. OK, problem solved - why am I still here? Well.... I'd like a more "elegant" solution, or at least one that is faster (ie. I don't want to get on with "real" work, I'd like to have some fun with this!). The best way I can think of is a ray-tracing approach - eg: from xmin to xmax, at y=ymin, check if data boundary crossed in intervals dx y=ymin+dy, do 1 do 1-2, but now sample in y An alternative is defining a centre, and sampling in r-theta space - ie radial spokes in dtheta increments. Both would produce a set of (x,y) points, but then how do I order/link neighbouring points them to create the boundary? A nearest neighbour approach is not appropriate as, for example (to borrow from Geography), an isthmus (think of Panama connecting N&S America) could then close off and isolate regions. This also might not deal very well with the holes seen in the data, which I would like to represent as a different plt.Polygon. The solution perhaps comes from solving an area maximisation problem. For a set of points defining the data limits, what is the maximum contiguous area contained within those points To form the enclosed area, what are the neighbouring points for the nth point? How will the holes be treated in this scheme - is this erring into topology now? Apologies, much of this is me thinking out loud. I'd be grateful for some hints, suggestions or solutions. I suspect this is an oft-studied problem with many solution techniques, but I'm looking for something simple to code and quick to run... I guess everyone is, really! Cheers, David

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• What would you suggest as a high school first language?

  - by ldigas

  Edit by OA: After reading some answers I'll just update the question a little. At first I put it a little bluntly, but some of those gave me some good arguments which have to be taken into consideration while making a stand on this one. (these are mostly picked up from comments and answers below). A few things to take into account: to many pupils this is a first programming language - at this stage most of them have trouble grasping a difference between data types, variable passing, ... and whatnot, less alone pointers and similar 'low level stuff' :) they will all have to pass this to get into next grade (well, big majority of them anyway) not all of them have computers at home, not all of them are willing to learn this, less alone interested in - so the concepts have to be taught on a finite time scale in school hours (as well as practice on computers) free literature is a bonus - the teacher will make some scripts and handaways, but still ... I wouldn't like to bear the parents with the burden of buying expensive literature (also, english is not a native language here ... and although they are all learning it, their ability to read it fluently is somewhat questionable) somebody gave an argument - "a language which does not get in the way of ideas" - good one accessibility on different platforms in not expecially important at this point - although most of the suggested ones are available on win as well as linux - not many macs in this part of europe (their prices are sky high for anything but specialised usage) I will check what are the licencing issues on ms express editions about using it massively in high schools for purposes like this - if someone has any info about this, please, do not be shy with it :) A friend of mine, informatics teacher - in EU it comes as something as junior cs teacher, in a local high school asked me what I thought about what should be the first language pupils should be taught? It is a technical school (a little more oriented towards mathematics than the gymnasium, but not computer oriented totally). So I'm asking you - what do you think should be the first language pupils are exposed to in highschool? They have been teaching Pascal so far, but she's not sure that's a good course. She thought about switching to C (which I resented; considering not all pupils have interests in programming, to start with, and should be taught something higher level since they are just gripping the idea of a loop and such ... for a start), I suggested python or ruby (preferably py since it handles all paradigms). What is your opinion on this one? I looked, but didn't find a similar question on SO, so if there is one, please just point me towards it. Edit: The assumption is that none of the pupils have been exposed to any programming in junior school. See also: What is the best way to teach young kids some basic programming concepts? Best ways to teach a beginner to program How and when do you teach a kid to code What is the easiest language to start with? High School Programming

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• How to store multiple variables from a File Input of unknown size in Java?

  - by AlphaOmegaStrife

  I'm a total beginner with my first programming assignment in Java. For our programming assignment, we will be given a .txt file of students like so: 3 345 Lisa Miller 890238 Y 2 <-(Number of classes) Mathematics MTH345 4 A Physics PHY357 3 B Bill Wilton 798324 N 2 English ENG378 3 B Philosophy PHL534 3 A Dandy Goat 746333 Y 1 History HIS101 3 A" The teacher will give us a .txt file on the day of turning it in with a list of unknown students. My problem is: I have a specific class for turning the data from the file into variables to be used for a different class in printing it to the screen. However, I do not know of a good way to get the variables from the input file for the course numbers, since that number is not predetermined. The only way I can think of to iterate over that unknown amount is using a loop, but that would just overwrite my variables every time. Also, the teacher has requested that we not use any JCL classes (I don't really know what this means.) Sorry if I have done a poor job of explaining this, but I can't think of a better way to conceptualize it. Let me know if I can clarify. Edit: public static void analyzeData() { Scanner inputStream = null; try { inputStream = new Scanner(new FileInputStream("Programming Assignment 1 Data.txt")); } catch (FileNotFoundException e) { System.out.println("File Programming Assignment 1 Data.txt could not be found or opened."); System.exit(0); } int numberOfStudents = inputStream.nextInt(); int tuitionPerHour = inputStream.nextInt(); String firstName = inputStream.next(); String lastname = inputStream.next(); String isTuitionPaid = inputStream.next(); int numberOfCourses = inputStream.nextInt(); String courseName = inputStream.next(); String courseNumber = inputStream.next(); int creditHours = inputStream.nextInt(); String grade = inputStream.next(); To show the methods I am using now, I am just using a Scanner to read from the file and for Scanner inputStream, I am using nextInt() or next() to get variables from the file. Obviously this will not work when I do not know exactly how many classes each student will have.

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• Adaptive ADF/WebCenter template for the iPad

  - by Maiko Rocha

  One of my WebCenter Portal customers was asking about adaptive design with ADF/WebCenter Portal and how they could go about creating an adaptive iPad template for their WebCenter Portal application. They were looking not only for the out-of-the-box support for mobile Safari which is certified against PS5+ (11.1.1.6) for ADF/WebCenter - but also to create a specific template to streamline their workflow on the iPad. Seems like they wanted something in the lines of Yahoo! Mail provides for the iPad - so the example I will use is shamelessly inspired by Y! Mail's iPad UI.  But first, let's quickly understand how can we bake in some adaptive goodness into ADF Faces. First thing we need to understand is, yes, there are a couple of constraints that we will need to work around, namely, the use or layout managers and skins. Please also keep in mind that I'm not and I don't pretend to be a web designer, much less an UX specialist, so feel free to leave your thoughts on the matter in the comments section. Now, back to the limitations. Layout Managers ADF Faces layout managers create an abstraction on top of the generated HTML code for a page so a developer doesn't need to be worried about how to size and dimension the UI layout (eg, af:panelStretchLayout). Although layout managers are very helpful, in this specific situation we will need to know a little bit more of how the final HTML is being rendered so we can apply the CSS class accordingly and create transition containers where the media queries will be applied - now, if you're using 11gR2 (11.1.2.2.3) there's the new component af:panelGridLayout (here and here) that will greatly improve creating responsive templates and pages because it is based on the grid/fluid systems and will generate straight out to DIVs on your final page. For now, I'm limited to PS5 and the af:panelStretchLayout component as a starting point because that's the release my customer is on. Skins You won't be able to use media queries, or use anything with "@" notation on the skin CSS file - the skin pre-processor will remove all extraneous "@" from the CSS file. The solution is to split your CSS in two separate files: a skin CSS file and plain CSS where you will add the media queries. The issue here is that you won't be able to use media queries for any faces components. We can, though, still apply the media queries for the components like af:panelGroupLayout and af:panelBorderLayout through their styleClass property to enable these components to be responsive to to the iPad orientation, by changing its dimensions, font sizes, hide/show areas, etc. Difference between responsive and adaptive design The best definition of adaptive vs responsive web design I could find is this: “Responsive web design,” as coined by Ethan Marcotte, means “fluid grids, fluid images/media & media queries.” “Adaptive web design,” as I use it, is about creating interfaces that adapt to the user’s capabilities (in terms of both form and function). To me, “adaptive web design” is just another term for “progressive enhancement” of which responsive web design can (an often should) be an integral part, but is a more holistic approach to web design in that it also takes into account varying levels of markup, CSS, JavaScript and assistive technology support. Responsive/adapative web design is much more than slapping an HTML template with CSS around your content or application. The content and application themselves are part of your web design - in other words, a responsive template is just an afterthought if it is not originating from a responsive design the involves the whole web application/s. Tips on responsive / adapative design with ADF/WebCenter Some of the tips listed below were already mentioned in multiple blog posts about ADF layout and skinning, but it is still worth remembering: a simple guideline for ADF/WebCenter apps would be to first create a high-level group of devices, for example: smartphones, tablets,  and desktop. For each of these large groups, create the basic structure to provide responsiveness: a page template, a skin, and an external CSS: pagetemplate_smartphone.jspx, smartphone_skin.css, smartphone-responsive.css pagetemplate_tablet.jspx, tablet_skin.css, tablet-responsive.css pagetemplate_desktop.jspx, desktop_skin.css, desktop-responsive.css These three assets can be changed on the fly through an user-agent check on the server side, delivering the right UI to the right device. Within each of the assets, you can make fine adjustments for each subgroup of devices with media queries - for example, smart phones with different screen dimensions and pixel density. Having these three groups and the corresponding assets per group seem to be a good compromise between trying to put everything on a single set of assets - specially considering the constraints above - and going to the other side of the spectrum to create assets per discrete device (iPhone4, iPhone5, Nexus, S3, etc.). Keep in mind that these are my rules and are not in any shape or form a best practice - this is how it fits best for the scenarios I've been working with. If you need to use HTML tags on your page, surround them with af:group to protect the DOM structure For stretchable/fluid layouts: Use non-stretching containers: panelGroupLayout, panelBorderLayout, … panelBorderLayout can be used to approximate HTML table component To avoid multiple scroll bars, do not nest scrolling PanelGroupLayout components. Consider layout="vertical" For stretchable/fluid layouts: Most stretchable ADF components also work in flowing context with dimensionsFrom="auto" To stretch a component horizontally, use styleClass="AFStretchWidth" instead of  "width:100%" Skinning Don't use CSS3 @media, @import, animations, etc. on skin css files. They will be removed. CSS3 properties within a class (box-shadow, transition, etc.) work just fine. Consider resetting some skin classes to better control their rendering: body {color: inherit;font: inherit;} af|document {-tr-inhibit: all;} af|commandLink {-tr-inhibit: all;} af|goLink {-tr-inhibit: all;} af|inputText::content {font: inherit;} Specific meta tags and CSS properties: Use  <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0"/> to avoid zooming (if you want) Use -webkit-overflow-scrolling: touch to enable native momentum scrolling within overflown areas (here) Use text-rendering: optmizeLegibility to improve readability. (here) User text-overflow: ellipsis to gracefully crop overflown text. (here) The meta-tags are included in each and every page in the metaContainer facet of af:document tag. You can also use a javascript to inject the meta-tags from the template. For the purpose of the example, I wanted to use as few workarounds as possible.   The iPad template and sample application This sample application has been built as a WebCenter Portal application, but you will also be able to reuse the template and techniques on your vanilla ADF application. Keep in mind that I'm neither a designer nor a CSS specialist, so please don't bash me too much on the messy CSS file you'll find on the application.  I've extended the provided PreferencesBean class that comes with WebCenter Portal and added code to dinamically change the template and skin on the fly.   This is the sample application in landscape orientation: This is the sample application in portrait orientation - the left side menu hides automatically based on a CSS media query: Another screenshot with a skinned popup opened: This is a sample application for you to play with - ideally you shouldn't use it as a starting point. On the left side bar you will find links rendered from a WebCenter Portal navigation model - the link triggers a full request through an af:goLink, while the light blue PPR button triggers a PPR navigation. The dark blue toolbar buttons at the top don't have any function,while the Approve and Reject buttons show a skinned popup. The search box of course doesn't have any behavior attahed to it either. There's a known issue right now with some PPR calls that are randomly generating a 403 error redirecting to the login page - I didn't have time to investigate if this is iOS6 specific or not - if you have any insights please let me know your findings. You can download the sample here.

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• CodePlex Daily Summary for Sunday, June 06, 2010

  CodePlex Daily Summary for Sunday, June 06, 2010New ProjectsActive Worlds Dot Net Wrapper (Based on AwSdk): Active Worlds Dot Net Wrapper (Based on AwSdk)Combina: Smart calculator for large combinatorial calculations.Concurrent Cache: ConcurrentCache is a smart output cache library extending OutputCacheProvider. It consists of in memory, cache files and compressed files modes and...Decay: Personal use. For learningFazTalk: FazTalk is a suite of tools and products that are designed to improve collaboration and workflow interactions. FazTalk takes an innovative approach...grouped: A peer to peer text editor, written in C# [update] I wrote this little thing a while back and even forgot about it, I stopped coding for more tha...HitchARide MVC 2 Sample: An MVC 2 sample written as part of the Microsoft 2010 London Web Camp based on the wireframes at http://schematics.earthware.co.uk/hitcharide. Not...Inspiration.Web: Description: A simple (but entertaining) ASP.NET MVC (C#) project to suggest random code names for projects. Intended audience: People who ne...NetFileBrowser - TinyMCE: tinyMCE file plugin with asp.netOil Slick Live Feeds: All live feeds from BP's Remotely Operated VehiclesParticle Lexer: Parser and Tokenizer libraryPdf Form Tool: Pdf Form Tool demonstrates how the iTextSharp library could be used to fill PDF forms. The input data is provided as a csv file. The application ...Planning Poker Windows Mobile 7: This project is a Planning Poker application for Windows Mobile 7 (and later?). RandomRat: RandomRat is a program for generating random sets that meet specific criteriaScience.NET: A scientific library written in managed code. It supports advanced mathematics (algebra system, sequences, statistics, combinatorics...), data stru...Spider Compiler: Spider Compiler parses the input of a spider programming source file and compiles it (with help of csc.exe; the C#-Compiler) to an exe-file. This p...Sununpro: sunun's project for study by team foundation server.TFS Buddy: An application that manipulates your I-Buddy whenever something happens in your Team Foundation ServerValveSoft: ValveSysWiiMote Physics: WiiMote Physics is an application that allows you to retrieve data from your WiiMote or Balance Board and display it in real-time. It has a number...WinGet: WinGet is a download manager for Windows. You can drag links onto the WinGet Widget and it will download a file on the selected folder. It is dev...XProject.NET: A project management and team collaboration platformNew Releases.NET DiscUtils: Version 0.9 Preview: This release is still under development. New features available in this release: Support for accessing short file names stored in WIM files Incr...Active Worlds Dot Net Wrapper (Based on AwSdk): Active World Dot Net Wrapper (0.0.1.85): Based on AwSdk 85AwSdk UnOfficial Wrapper Howto Use: C# using AwWrapper; VB.Net Import AwWrapperAjaxControlToolkit additional extenders: ZhecheAjaxControls for .NET3.5: Used AJAX Control Toolkit Release Notes - April 12th 2010 Release Version 40412. Fixed deadlock in long operation canceling Some other fixesAnyCAD: AnyCAD.v1.2.ENU.Install: http://www.anycad.net Parametric Modeling *3D: Sphere, Box, Cylinder, Cone •2D: Line, Rectangle, Arc, Arch, Circle, Spline, Polygon •Feature: Extr...Community Forums NNTP bridge: Community Forums NNTP Bridge V29: Release of the Community Forums NNTP Bridge to access the social and anwsers MS forums with a single, open source NNTP bridge. This release has ad...Concurrent Cache: 1.0: This is the first release for the ConcurrentCache library.Configuration Section Designer: 2.0.0: This is the first Beta Release for VS 2010 supportDoxygen Browser Addin for VS: Doxygen Browser Addin - v0.1.4 Beta: Support for Visual Studio 2010 improved the logging of errors (Event Logs) Fixed some issues/bugs Hot key for navigation "Control + F1, Contr...Folder Bookmarks: Folder Bookmarks 1.6.2: The latest version of Folder Bookmarks (1.6.2), with new UI changes. Once you have extracted the file, do not delete any files/folders. They are n...HERB.IQ: Beta 0.1 Source code release 5: Beta 0.1 Source code release 5Inspiration.Web: Initial release (deployment package): Initial release (deployment package)NetFileBrowser - TinyMCE: Demo Project: Demo ProjectNetFileBrowser - TinyMCE: NetFileBrowser: NetImageBrowserNLog - Advanced .NET Logging: Nightly Build 2010.06.05.001: Changes since the last build:2010-06-04 23:29:42 Jarek Kowalski Massive update to documentation generator. 2010-05-28 15:41:42 Jarek Kowalski upda...Oil Slick Live Feeds: Oil Slick Live Feeds 0.1: A the first release, with feeds from the MS Skandi, Boa Deep C, Enterprise and Q4000. They are live streams from the ROV's monitoring the damaged...Pcap.Net: Pcap.Net 0.7.0 (46671): Pcap.Net - June 2010 Release Pcap.Net is a .NET wrapper for WinPcap written in C++/CLI and C#. It Features almost all WinPcap features and includes...sqwarea: Sqwarea 0.0.289.0 (alpha): API supportTFS Buddy: TFS Buddy First release (Beta 1): This is the first release of the TFS Buddy.Visual Studio DSite: Looping Animation (Visual C++ 2008): A solider firing a bullet that loops and displays an explosion everytime it hits the edge of the form.WiiMote Physics: WiiMote Physics v4.0: v4.0.0.1 Recovered from existing compiled assembly after hard drive failure Now requires .NET 4.0 (it seems to make it run faster) Added new c...WinGet: Alpha 1: First Alpha of WinGet. It includes all the planned features but it contains many bugs. Packaged using 7-Zip and ClickOnce.Most Popular ProjectsWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)PHPExcelpatterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesASP.NETMost Active ProjectsCommunity Forums NNTP bridgeRawrpatterns & practices – Enterprise LibraryGMap.NET - Great Maps for Windows Forms & PresentationN2 CMSIonics Isapi Rewrite FilterStyleCopsmark C# LibraryFarseer Physics Enginepatterns & practices: Composite WPF and Silverlight

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• Using the BAM Interceptor with Continuation

  - by Charles Young

  Originally posted on: http://geekswithblogs.net/cyoung/archive/2014/06/02/using-the-bam-interceptor-with-continuation.aspxI’ve recently been resurrecting some code written several years ago that makes extensive use of the BAM Interceptor provided as part of BizTalk Server’s BAM event observation library.  In doing this, I noticed an issue with continuations.  Essentially, whenever I tried to configure one or more continuations for an activity, the BAM Interceptor failed to complete the activity correctly.   Careful inspection of my code confirmed that I was initializing and invoking the BAM interceptor correctly, so I was mystified.  However, I eventually found the problem.  It is a logical error in the BAM Interceptor code itself. The BAM Interceptor provides a useful mechanism for implementing dynamic tracking.  It supports configurable ‘track points’.  These are grouped into named ‘locations’.  BAM uses the term ‘step’ as a synonym for ‘location’.   Each track point defines a BAM action such as starting an activity, extracting a data item, enabling a continuation, etc.  Each step defines a collection of track points. Understanding Steps The BAM Interceptor provides an abstract model for handling configuration of steps.  It doesn’t, however, define any specific configuration mechanism (e.g., config files, SSO, etc.)  It is up to the developer to decide how to store, manage and retrieve configuration data.  At run time, this configuration is used to register track points which then drive the BAM Interceptor. The full semantics of a step are not immediately clear from Microsoft’s documentation.  They represent a point in a business activity where BAM tracking occurs.  They are named locations in the code.  What is less obvious is that they always represent either the full tracking work for a given activity or a discrete fragment of that work which commences with the start of a new activity or the continuation of an existing activity.  The BAM Interceptor enforces this by throwing an error if no ‘start new’ or ‘continue’ track point is registered for a named location. This constraint implies that each step must marked with an ‘end activity’ track point.  One of the peculiarities of BAM semantics is that when an activity is continued under a correlated ID, you must first mark the current activity as ‘ended’ in order to ensure the right housekeeping is done in the database.  If you re-start an ended activity under the same ID, you will leave the BAM import tables in an inconsistent state.  A step, therefore, always represents an entire unit of work for a given activity or continuation ID.  For activities with continuation, each unit of work is termed a ‘fragment’. Instance and Fragment State Internally, the BAM Interceptor maintains state data at two levels.  First, it represents the overall state of the activity using a ‘trace instance’ token.  This token contains the name and ID of the activity together with a couple of state flags.  The second level of state represents a ‘trace fragment’.   As we have seen, a fragment of an activity corresponds directly to the notion of a ‘step’.  It is the unit of work done at a named location, and it must be bounded by start and end, or continue and end, actions. When handling continuations, the BAM Interceptor differentiates between ‘root’ fragments and other fragments.  Very simply, a root fragment represents the start of an activity.  Other fragments represent continuations.  This is where the logic breaks down.  The BAM Interceptor loses state integrity for root fragments when continuations are defined. Initialization Microsoft’s BAM Interceptor code supports the initialization of BAM Interceptors from track point configuration data.  The process starts by populating an Activity Interceptor Configuration object with an array of track points.  These can belong to different steps (aka ‘locations’) and can be registered in any order.  Once it is populated with track points, the Activity Interceptor Configuration is used to initialise the BAM Interceptor.  The BAM Interceptor sets up a hash table of array lists.  Each step is represented by an array list, and each array list contains an ordered set of track points.  The BAM Interceptor represents track points as ‘executable’ components.  When the OnStep method of the BAM Interceptor is called for a given step, the corresponding list of track points is retrieved and each track point is executed in turn.  Each track point retrieves any required data using a call back mechanism and then serializes a BAM trace fragment object representing a specific action (e.g., start, update, enable continuation, stop, etc.).  The serialised trace fragment is then handed off to a BAM event stream (buffered or direct) which takes the appropriate action. The Root of the Problem The logic breaks down in the Activity Interceptor Configuration.  Each Activity Interceptor Configuration is initialised with an instance of a ‘trace instance’ token.  This provides the basic metadata for the activity as a whole.  It contains the activity name and ID together with state flags indicating if the activity ID is a root (i.e., not a continuation fragment) and if it is completed.  This single token is then shared by all trace actions for all steps registered with the Activity Interceptor Configuration. Each trace instance token is automatically initialised to represent a root fragment.  However, if you subsequently register a ‘continuation’ step with the Activity Interceptor Configuration, the ‘root’ flag is set to false at the point the ‘continue’ track point is registered for that step.   If you use a ‘reflector’ tool to inspect the code for the ActivityInterceptorConfiguration class, you can see the flag being set in one of the overloads of the RegisterContinue method.    This makes no sense.  The trace instance token is shared across all the track points registered with the Activity Interceptor Configuration.  The Activity Interceptor Configuration is designed to hold track points for multiple steps.  The ‘root’ flag is clearly meant to be initialised to ‘true’ for the preliminary root fragment and then subsequently set to false at the point that a continuation step is processed.  Instead, if the Activity Interceptor Configuration contains a continuation step, it is changed to ‘false’ before the root fragment is processed.  This is clearly an error in logic. The problem causes havoc when the BAM Interceptor is used with continuation.  Effectively the root step is no longer processed correctly, and the ultimate effect is that the continued activity never completes!   This has nothing to do with the root and the continuation being in the same process.  It is due to a fundamental mistake of setting the ‘root’ flag to false for a continuation before the root fragment is processed. The Workaround Fortunately, it is easy to work around the bug.  The trick is to ensure that you create a new Activity Interceptor Configuration object for each individual step.  This may mean filtering your configuration data to extract the track points for a single step or grouping the configured track points into individual steps and the creating a separate Activity Interceptor Configuration for each group.  In my case, the first approach was required.  Here is what the amended code looks like: // Because of a logic error in Microsoft's code, a separate ActivityInterceptorConfiguration must be used // for each location. The following code extracts only those track points for a given step name (location). var trackPointGroup = from ResolutionService.TrackPoint tp in bamActivity.TrackPoints                       where (string)tp.Location == bamStepName                       select tp; var bamActivityInterceptorConfig =     new Microsoft.BizTalk.Bam.EventObservation.ActivityInterceptorConfiguration(activityName); foreach (var trackPoint in trackPointGroup) {     switch (trackPoint.Type)     {         case TrackPointType.Start:             bamActivityInterceptorConfig.RegisterStartNew(trackPoint.Location, trackPoint.ExtractionInfo);             break; etc… I’m using LINQ to filter a list of track points for those entries that correspond to a given step and then registering only those track points on a new instance of the ActivityInterceptorConfiguration class.   As soon as I re-wrote the code to do this, activities with continuations started to complete correctly.

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• The Data Scientist

  - by BuckWoody

  A new term - well, perhaps not that new - has come up and I’m actually very excited about it. The term is Data Scientist, and since it’s new, it’s fairly undefined. I’ll explain what I think it means, and why I’m excited about it. In general, I’ve found the term deals at its most basic with analyzing data. Of course, we all do that, and the term itself in that definition is redundant. There is no science that I know of that does not work with analyzing lots of data. But the term seems to refer to more than the common practices of looking at data visually, putting it in a spreadsheet or report, or even using simple coding to examine data sets. The term Data Scientist (as far as I can make out this early in it’s use) is someone who has a strong understanding of data sources, relevance (statistical and otherwise) and processing methods as well as front-end displays of large sets of complicated data. Some - but not all - Business Intelligence professionals have these skills. In other cases, senior developers, database architects or others fill these needs, but in my experience, many lack the strong mathematical skills needed to make these choices properly. I’ve divided the knowledge base for someone that would wear this title into three large segments. It remains to be seen if a given Data Scientist would be responsible for knowing all these areas or would specialize. There are pretty high requirements on the math side, specifically in graduate-degree level statistics, but in my experience a company will only have a few of these folks, so they are expected to know quite a bit in each of these areas. Persistence The first area is finding, cleaning and storing the data. In some cases, no cleaning is done prior to storage - it’s just identified and the cleansing is done in a later step. This area is where the professional would be able to tell if a particular data set should be stored in a Relational Database Management System (RDBMS), across a set of key/value pair storage (NoSQL) or in a file system like HDFS (part of the Hadoop landscape) or other methods. Or do you examine the stream of data without storing it in another system at all? This is an important decision - it’s a foundation choice that deals not only with a lot of expense of purchasing systems or even using Cloud Computing (PaaS, SaaS or IaaS) to source it, but also the skillsets and other resources needed to care and feed the system for a long time. The Data Scientist sets something into motion that will probably outlast his or her career at a company or organization. Often these choices are made by senior developers, database administrators or architects in a company. But sometimes each of these has a certain bias towards making a decision one way or another. The Data Scientist would examine these choices in light of the data itself, starting perhaps even before the business requirements are created. The business may not even be aware of all the strategic and tactical data sources that they have access to. Processing Once the decision is made to store the data, the next set of decisions are based around how to process the data. An RDBMS scales well to a certain level, and provides a high degree of ACID compliance as well as offering a well-known set-based language to work with this data. In other cases, scale should be spread among multiple nodes (as in the case of Hadoop landscapes or NoSQL offerings) or even across a Cloud provider like Windows Azure Table Storage. In fact, in many cases - most of the ones I’m dealing with lately - the data should be split among multiple types of processing environments. This is a newer idea. Many data professionals simply pick a methodology (RDBMS with Star Schemas, NoSQL, etc.) and put all data there, regardless of its shape, processing needs and so on. A Data Scientist is familiar not only with the various processing methods, but how they work, so that they can choose the right one for a given need. This is a huge time commitment, hence the need for a dedicated title like this one. Presentation This is where the need for a Data Scientist is most often already being filled, sometimes with more or less success. The latest Business Intelligence systems are quite good at allowing you to create amazing graphics - but it’s the data behind the graphics that are the most important component of truly effective displays. This is where the mathematics requirement of the Data Scientist title is the most unforgiving. In fact, someone without a good foundation in statistics is not a good candidate for creating reports. Even a basic level of statistics can be dangerous. Anyone who works in analyzing data will tell you that there are multiple errors possible when data just seems right - and basic statistics bears out that you’re on the right track - that are only solvable when you understanding why the statistical formula works the way it does. And there are lots of ways of presenting data. Sometimes all you need is a “yes” or “no” answer that can only come after heavy analysis work. In that case, a simple e-mail might be all the reporting you need. In others, complex relationships and multiple components require a deep understanding of the various graphical methods of presenting data. Knowing which kind of chart, color, graphic or shape conveys a particular datum best is essential knowledge for the Data Scientist. Why I’m excited I love this area of study. I like math, stats, and computing technologies, but it goes beyond that. I love what data can do - how it can help an organization. I’ve been fortunate enough in my professional career these past two decades to work with lots of folks who perform this role at companies from aerospace to medical firms, from manufacturing to retail. Interestingly, the size of the company really isn’t germane here. I worked with one very small bio-tech (cryogenics) company that worked deeply with analysis of complex interrelated data. So  watch this space. No, I’m not leaving Azure or distributed computing or Microsoft. In fact, I think I’m perfectly situated to investigate this role further. We have a huge set of tools, from RDBMS to Hadoop to allow me to explore. And I’m happy to share what I learn along the way.

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