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  • Suggested Web Application Framework and Database for Enterprise, “Big-Data” App?

    - by willOEM
    I have a web application that I have been developing for a small group within my company over the past few years, using Pipeline Pilot (plus jQuery and Python scripting) for web development and back-end computation, and Oracle 10g for my RDBMS. Users upload experimental genomic data, which is parsed into a database, and made available for querying, transformation, and reporting. Experimental data sets are large and have many layers of metadata. A given experimental data record might have a foreign key relationship with a table that describes this data point's assay. Assays can cover multiple genes, which can have multiple transcript, which can have multiple mutations, which can affect multiple signaling pathways, etc. Users need to approach this data from any point in those layers in the metadata. Since all data sets for a given data type can run over a billion rows, this results in some large, dynamic queries that are hard to predict. New data sets are added on a weekly basis (~1GB per set). Experimental data is never updated, but the associated metadata can be updated weekly for a few records and yearly for most others. For every data set insert the system sees, there will be between 10 and 100 selects run against it and associated data. It is okay for updates and inserts to run slow, so long as queries run quick and are as up-to-date as possible. The application continues to grow in size and scope and is already starting to run slower than I like. I am worried that we have about outgrown Pipeline Pilot, and perhaps Oracle (as the sole database). Would a NoSQL database or an OLAP system be appropriate here? What web application frameworks work well with systems like this? I'd like the solution to be something scalable, portable and supportable X-years down the road. Here is the current state of the application: Web Server/Data Processing: Pipeline Pilot on Windows Server + IIS Database: Oracle 10g, ~1TB of data, ~180 tables with several billion-plus row tables Network Storage: Isilon, ~50TB of low-priority raw data

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  • Big numbers in C

    - by teehoo
    I need help working with very big numbers. According to Windows calc, the exponent 174^55 = 1.6990597648061509725749329578093e+123. How would I store this using C (c99 standard). int main(){ long long int x = 174^55; //result is 153 printf("%lld\n", x); } For those curious, it is for a school project where we are implementing the RSA cryptographic algorithm, which deals with exponentiating large numbers with large powers for encryption/decryption.

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  • Big O, how do you calculate/approximate it?

    - by Sven
    Most people with a degree in CS will certainly know what Big O stands for. It helps us to measure how (in)efficient an algorithm really is and if you know in what category the problem you are trying to solve lays in you can figure out if it is still possible to squeeze out that little extra performance.* But I'm curious, how do you calculate or approximate the complexity of your algorithms? *: but as they say, don't overdo it, premature optimization is the root of all evil, and optimization without a justified cause should deserve that name as well.

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  • How big is too big (for NTFS)

    - by BCS
    I have a program and as it's done now, it has a data directory with something like 10-30K files in it and it's starting to cause problems. Should I expect that to cause problems and my only solution to tweak my file structure or does that indicate other problems?

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  • Big O and Little o

    - by hyperdude
    If algorithm A has complexity O(n) and algorithm B has complexity o(n^2), what, if anything, can we say about the relationship between A and B? Note: the complexity of A is expressed using big-Oh, and the complexity of B is expressed using little-Oh.

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  • BIG DATA eBook - Now Available

    - by Javier Puerta
    The Big Data interactive e-book “Meeting the Challenge of Big Data: Part One” has just been released. It’s your “one-stop shop” for info about Big Data and the Oracle offering around it.The new e-book (available on your computer or iPad) is packed with multi-media resources to educate Oracle staff, customers, prospects and partners on the value of Big Data. It features videos, tutorials, podcasts, reports, white papers, datasheets, blogs, web links, a 3-D demo, and more. Go and get it here!

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  • Big Data Sessions at Openworld 2012

    - by Jean-Pierre Dijcks
    If you are coming to San Francisco, and you are interested in all the aspects to big data, this Focus On Big Data is a must have document.  Some (other) highlights: A performance demo of a full rack Big Data Appliance in the engineered systems showcase A set of handson labs on how to go from a NoSQL DB to an effective analytics play on big data Much, much more See you all in a few weeks in SF!

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  • Big Oh Notation - formal definition.

    - by aloh
    I'm reading a textbook right now for my Java III class. We're reading about Big-Oh and I'm a little confused by its formal definition. Formal Definition: "A function f(n) is of order at most g(n) - that is, f(n) = O(g(n)) - if a positive real number c and positive integer N exist such that f(n) <= c g(n) for all n = N. That is, c g(n) is an upper bound on f(n) when n is sufficiently large." Ok, that makes sense. But hold on, keep reading...the book gave me this example: "In segment 9.14, we said that an algorithm that uses 5n + 3 operations is O(n). We now can show that 5n + 3 = O(n) by using the formal definition of Big Oh. When n = 3, 5n + 3 <= 5n + n = 6n. Thus, if we let f(n) = 5n + 3, g(n) = n, c = 6, N = 3, we have shown that f(n) <= 6 g(n) for n = 3, or 5n + 3 = O(n). That is, if an algorithm requires time directly proportional to 5n + 3, it is O(n)." Ok, this kind of makes sense to me. They're saying that if n = 3 or greater, 5n + 3 takes less time than if n was less than 3 - thus 5n + n = 6n - right? Makes sense, since if n was 2, 5n + 3 = 13 while 6n = 12 but when n is 3 or greater 5n + 3 will always be less than or equal to 6n. Here's where I get confused. They give me another example: Example 2: "Let's show that 4n^2 + 50n - 10 = O(n^2). It is easy to see that: 4n^2 + 50n - 10 <= 4n^2 + 50n for any n. Since 50n <= 50n^2 for n = 50, 4n^2 + 50n - 10 <= 4n^2 + 50n^2 = 54n^2 for n = 50. Thus, with c = 54 and N = 50, we have shown that 4n^2 + 50n - 10 = O(n^2)." This statement doesn't make sense: 50n <= 50n^2 for n = 50. Isn't any n going to make the 50n less than 50n^2? Not just greater than or equal to 50? Why did they even mention that 50n <= 50n^2? What does that have to do with the problem? Also, 4n^2 + 50n - 10 <= 4n^2 + 50n^2 = 54n^2 for n = 50 is going to be true no matter what n is. And how in the world does picking numbers show that f(n) = O(g(n))? Please help me understand! :(

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  • Which tool can list writing access to a specific variable in C?

    - by Lichtblitz
    Unfortunately I'm not even sure how this sort of static analysis is called. It's not really control flow analysis because I'm not looking for function calls and I don't really need data flow analysis because I don't care about the actual values. I just need a tool that lists the locations (file, function) where writing access to a specific variable takes place. I don't even care if that list contained lines that are unreachable. I could imagine that writing a simple parser could suffice for this task but I'm certain that there must be a tool out there that does this simple analysis. As a poor student I would appreciate free or better yet open source tools and if someone could tell me how this type of static analysis is actually called, I would be equally grateful! EDIT: I forgot to mention there's no pointer arithmetic in the code base.

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  • Big O Complexity of a method

    - by timeNomad
    I have this method: public static int what(String str, char start, char end) { int count=0; for(int i=0;i<str.length(); i++) { if(str.charAt(i) == start) { for(int j=i+1;j<str.length(); j++) { if(str.charAt(j) == end) count++; } } } return count; } What I need to find is: 1) What is it doing? Answer: counting the total number of end occurrences after EACH (or is it? Not specified in the assignment, point 3 depends on this) start. 2) What is its complexity? Answer: the first loops iterates over the string completely, so it's at least O(n), the second loop executes only if start char is found and even then partially (index at which start was found + 1). Although, big O is all about worst case no? So in the worst case, start is the 1st char & the inner iteration iterates over the string n-1 times, the -1 is a constant so it's n. But, the inner loop won't be executed every outer iteration pass, statistically, but since big O is about worst case, is it correct to say the complexity of it is O(n^2)? Ignoring any constants and the fact that in 99.99% of times the inner loop won't execute every outer loop pass. 3) Rewrite it so that complexity is lower. What I'm not sure of is whether start occurs at most once or more, if once at most, then method can be rewritten using one loop (having a flag indicating whether start has been encountered and from there on incrementing count at each end occurrence), yielding a complexity of O(n). In case though, that start can appear multiple times, which most likely it is, because assignment is of a Java course and I don't think they would make such ambiguity. Solving, in this case, is not possible using one loop... WAIT! Yes it is..! Just have a variable, say, inc to be incremented each time start is encountered & used to increment count each time end is encountered after the 1st start was found: inc = 0, count = 0 if (current char == start) inc++ if (inc > 0 && current char == end) count += inc This would also yield a complexity of O(n)? Because there is only 1 loop. Yes I realize I wrote a lot hehe, but what I also realized is that I understand a lot better by forming my thoughts into words...

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  • Static code analysis for VB6 and classic ASP

    - by Ryan
    I'm looking for a static code analysis tool that will determine if I have orphaned functions in my VB6 code. The problem I'm running into is we make calls to the VB6 code from classic asp. Is there a tool that will look at both the classic asp and VB6 and determine if there are any orphaned functions?

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  • Static code analysis tools for VB6

    - by Maksym Markov
    Right now we are maintaining some old project written in VB6 we are planning to implement continues integration sefver for it. We would like to implement some code analysis as well to track that maintanability at least not getting worse. Basically there is only one requirement - the tool should be command line so we can call it from constinues integration server and it should work with VB6 projects. I will really a;preciate any recommendations regards tools to try. Thank you, Maksym

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  • Code Analysis - Treat as Error

    - by Brian Schmitt
    Looking to enable the "Enable code Analysis on Build" feature in Visual Studio. Obviously the Rules are a best practice, and I am working with an existing code base that currently fails many of the rules. I am looking for input as to which rules are the most egregious and should be treated as an Error.

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  • Javascript source code analysis ( specifically duplication checking )

    - by David
    Partial duplicate of this Notes: I already use JSLint extensively via a tool I wrote that scans in intervals my current project directory for recently updated/created .js files. It's drastically improved productivity for me and I doubt there is anything as good as JSLint for the price (it's free). That said, is there any analysis tool out there that can find repetitive or near-duplicate code blocks, the goal being to make it easier to find opportunities to consolidate large files or small/medium sized projects?

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  • Glassfish log files analysis

    - by Cem
    Can I get some recommendations for good log analysis software for Glassfish log files? Since it will not vary from application server to application server dramatically, I guess that there is a common solution for all servers. Thanks

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  • .Net Analysis tools [closed]

    - by TWith2Sugars
    Possible Duplicate: What static analysis tools are available for C#? At work we tend to use two tools for analysing our projects, FxCop to analyse our managed code and StyleCop to have consistent code layout. I found these tools pretty much by accident and it has led me to wonder what other tools are available that I might of missed?

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  • Oracle Solaris Crash Analysis Tool 5.3 now available

    - by user12609056
    Oracle Solaris Crash Analysis Tool 5.3 The Oracle Solaris Crash Analysis Tool Team is happy to announce the availability of release 5.3.  This release addresses bugs discovered since the release of 5.2 plus enhancements to support Oracle Solaris 11 and updates to Oracle Solaris versions 7 through 10. The packages are available on My Oracle Support - simply search for Patch 13365310 to find the downloadable packages. Release Notes General blast support The blast GUI has been removed and is no longer supported. Oracle Solaris 2.6 Support As of Oracle Solaris Crash Analysis Tool 5.3, support for Oracle Solaris 2.6 has been dropped. If you have systems running Solaris 2.6, you will need to use Oracle Solaris Crash Analysis Tool 5.2 or earlier to read its crash dumps. New Commands Sanity Command Though one can re-run the sanity checks that are run at tool start-up using the coreinfo command, many users were unaware that they were. Though these checks can still be run using that command, a new command, namely sanity, can now be used to re-run the checks at any time. Interface Changes scat_explore -r and -t option The -r option has ben added to scat_explore so that a base directory can be specified and the -t op[tion was added to enable color taggging of the output. The scat_explore sub-command now accepts new options. Usage is: scat --scat_explore [-atv] [-r base_dir] [-d dest] [unix.N] [vmcore.]N Where: -v Verbose Mode: The command will print messages highlighting what it's doing. -a Auto Mode: The command does not prompt for input from the user as it runs. -d dest Instructs scat_explore to save it's output in the directory dest instead of the present working directory. -r base_dir Instructs scat_explore to save it's under the directory base_dir instead of the present working directory. If it is not specified using the -d option, scat_explore names it's output file as "scat_explore_system_name_hostid_lbolt_value_corefile_name." -t Enable color tags. When enabled, scat_explore tags important text with colors that match the level of importance. These colors correspond to the color normally printed when running Oracle Solaris Crash Analysis Tool in interactive mode. Tag Name Definition FATAL An extremely important message which should be investigated. WARNING A warning that may or may not have anything to do with the crash. ERROR An error, usually printer with a suggested command ALERT Used to indicate something the tool discovered. INFO Purely informational message INFO2 A follow-up to an INFO tagged message REDZONE Usually used when prnting memory info showing something is in the kernel's REDZONE. N The number of the crash dump. Specifying unix.N vmcore.N is optional and not required. Example: $ scat --scat_explore -a -v -r /tmp vmcore.0 #Output directory: /tmp/scat_explore_oomph_833a2959_0x28800_vmcore.0 #Tar filename: scat_explore_oomph_833a2959_0x28800_vmcore.0.tar #Extracting crash data... #Gathering standard crash data collections... #Panic string indicates a possible hang... #Gathering Hang Related data... #Creating tar file... #Compressing tar file... #Successful extraction SCAT_EXPLORE_DATA_DIR=/tmp/scat_explore_oomph_833a2959_0x28800_vmcore.0 Sending scat_explore results The .tar.gz file that results from a scat_explore run may be sent using Oracle Secure File Transfer. The Oracle Secure File Transfer User Guide describes how to use it to send a file. The send_scat_explore script now has a -t option for specifying a to address for sending the results. This option is mandatory. Known Issues There are a couple known issues that we are addressing in release 5.4, which you should expect to see soon: Display of timestamps in threads and clock information is incorrect in some cases. There are alignment issues with some of the tables produced by the tool.

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  • big O notation algorithm

    - by niggersak
    Use big-O notation to classify the traditional grade school algorithms for addition and multiplication. That is, if asked to add two numbers each having N digits, how many individual additions must be performed? If asked to multiply two N-digit numbers, how many individual multiplications are required? . Suppose f is a function that returns the result of reversing the string of symbols given as its input, and g is a function that returns the concatenation of the two strings given as its input. If x is the string hrwa, what is returned by g(f(x),x)? Explain your answer - don't just provide the result!

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  • Tricky Big-O complexity

    - by timeNomad
    public void foo (int n, int m) { int i = m; while (i > 100) i = i/3; for (int k=i ; k>=0; k--) { for (int j=1; j<n; j*=2) System.out.print(k + "\t" + j); System.out.println(); } } I figured the complexity would be O(logn). That is as a product of the inner loop, the outer loop -- will never be executed more than 100 times, so it can be omitted. What I'm not sure about is the while clause, should it be incorporated into the Big-O complexity? For very large i values it could make an impact, or arithmetic operations, doesn't matter on what scale, count as basic operations and can be omitted?

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  • Database indexes and their Big-O notation

    - by miket2e
    I'm trying to understand the performance of database indexes in terms of Big-O notation. Without knowing much about it, I would guess that: Querying on a primary key or unique index will give you a O(1) lookup time. Querying on a non-unique index will also give a O(1) time, albeit maybe the '1' is slower than for the unique index (?) Querying on a column without an index will give a O(N) lookup time (full table scan). Is this generally correct ? Will querying on a primary key ever give worse performance than O(1) ? My specific concern is for SQLite, but I'd be interested in knowing to what extent this varies between different databases too.

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  • Can someone help with big O notation?

    - by Dann
    void printScientificNotation(double value, int powerOfTen) { if (value >= 1.0 && value < 10.0) { System.out.println(value + " x 10^" + powerOfTen); } else if (value < 1.0) { printScientificNotation(value * 10, powerOfTen - 1); } else // value >= 10.0 { printScientificNotation(value / 10, powerOfTen + 1); } } I understand how the method goes but I cannot figure out a way to represent the method. For example, if value was 0.00000009 or 9e-8, the method will call on printScientificNotation(value * 10, powerOfTen - 1); eight times and System.out.println(value + " x 10^" + powerOfTen); once. So the it is called recursively by the exponent for e. But how do I represent this by big O notation? Thanks!

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