Search Results

Search found 14169 results on 567 pages for 'parallel programming'.

Page 35/567 | < Previous Page | 31 32 33 34 35 36 37 38 39 40 41 42  | Next Page >

  • Possible to distribute or parallel process a sequential program?

    - by damigu
    In C++, I've written a mathematical program (for diffusion limited aggregation) where each new point calculated is dependent on all of the preceding points. Is it possible to have such a program work in a parallel or distributed manner to increase computing speed? If so, what type of modifications to the code would I need to look into?

    Read the article

  • Serial plans: Threshold / Parallel_degree_limit = 1

    - by jean-pierre.dijcks
    As a very short follow up on the previous post. So here is some more on getting a serial plan and why that happens Another reason - compared to the auto DOP is not on as we looked at in the earlier post - and often more prevalent to get a serial plan is if the plan simply does not take long enough to consider a parallel path. The resulting plan and note looks like this (note that this is a serial plan!): explain plan for select count(1) from sales; SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY()); PLAN_TABLE_OUTPUT -------------------------------------------------------------------------------- Plan hash value: 672559287 -------------------------------------------------------------------------------------- | Id  | Operation            | Name  | Rows  | Cost (%CPU)| Time     | Pstart| Pstop | -------------------------------------------------------------------------------------- PLAN_TABLE_OUTPUT -------------------------------------------------------------------------------- |   0 | SELECT STATEMENT     |       |     1 |     5   (0)| 00:00:01 |       |     | |   1 |  SORT AGGREGATE      |       |     1 |            |          |       |     | |   2 |   PARTITION RANGE ALL|       |   960 |     5   (0)| 00:00:01 |     1 |  16 | |   3 |    TABLE ACCESS FULL | SALES |   960 |     5   (0)| 00:00:01 |     1 |  16 | Note -----    - automatic DOP: Computed Degree of Parallelism is 1 because of parallel threshold 14 rows selected. The parallel threshold is referring to parallel_min_time_threshold and since I did not change the default (10s) the plan is not being considered for a parallel degree computation and is therefore staying with the serial execution. Now we go into the land of crazy: Assume I do want this DOP=1 to happen, I could set the parameter in the init.ora, but to highlight it in this case I changed it on the session: alter session set parallel_degree_limit = 1; The result I get is: ERROR: ORA-02097: parameter cannot be modified because specified value is invalid ORA-00096: invalid value 1 for parameter parallel_degree_limit, must be from among CPU IO AUTO INTEGER>=2 Which of course makes perfect sense...

    Read the article

  • Embedded Prolog Interpreter/Compiler for Java

    - by Sami
    I'm working on an application in Java, that needs to do some complex logic rule deductions as part of its functionality. I'd like to code my logic deductions in Prolog or some other logic/constraint programming language, instead of Java, as I believe the resulting code will be significantly simpler and more maintainable. I Googled for embedded Java implementations on Prolog, and found number of them, each with very little documentation. My (modest) selection criteria are: should be embeddable in Java (e.g. can be bundled up with my java package instead of requiring any native installations on external programs) simple interface to use from Java (for initiating deductions, inspecting results, and adding rules) come with at least a few examples on how to use it doesn't necessarely have to be Prolog, but other logic/constraint programming languages with the above criteria would suit my needs, too. What choices do I have and what are their advantages and disadvantages?

    Read the article

  • Which useful alternative control structures do you know?

    - by bigown
    Similar question was closed on SO. Sometimes when we're programming, we find that some particular control structure would be very useful to us, but is not directly available in our programming language. What alternative control structures do you think are a useful way of organizing computation? The goal here is to get new ways of thinking about structuring code, in order to improve chunking and reasoning. You can create a wishful syntax/semantic not available now or cite a less known control structure on an existent programming language. Answers should give ideas for a new programming language or enhancing an actual language. Think of this as brainstorming, so post something you think is a crazy idea but it can be viable in some scenario. It's about imperative programming.

    Read the article

  • Parallel curve like algorithm for graphs

    - by skrat
    Is there a well know algorithm for calculating "parallel graph"? where by parallel graph I mean the same as parallel curve, vaguely called "offset curve", but with a graph instead of a curve. Given this picture how can I calculate points of black outlined polygons?

    Read the article

  • What is IE's Maximum Parallel Connection Accross All Hosts

    - by timeitquery
    Based on the IE documentation on MSDN IE 8 supports up to 6 parallel connections per server and IE 6,7 support 2. What is the upper limit of parallel connections accross all the hosts? So if I have 60 hosts, 8 requests per host, so 360 requests in the HTML page - does it mean that IE 8 will have 360 connection in parallel and IE 6 or 7 would have 120? (ignoring the html rendering time, and if call is blocking or not)

    Read the article

  • Draw a parallel line

    - by VOX
    I have x1,y1 and x2,y2 which forms a line segment. How can I get another line x3,y3 - x4,y4 which is parallel to the first line as in the picture. I can simply add n to x1 and x2 to get a parallel line but it is not what i wanted. I want the lines to be as parallel in the picture.

    Read the article

  • Parallel Assignment operator in Ruby

    - by Bragaadeesh
    Hi, I was going through an example from Programming in Ruby book. This is that example def fib_up_to(max) i1, i2 = 1, 1 # parallel assignment (i1 = 1 and i2 = 1) while i1 <= max yield i1 i1, i2 = i2, i1+i2 end end fib_up_to(100) {|f| print f, " " } The above program simply prints the fibonacci numbers upto 100. Thats fine. My question here is when i replace the parallel assignment with something like this, i1 = i2 i2 = i1+i2 I am not getting the desired output. My question here is, is it advisable to use parallel assignments? (I come from Java background and it feels really wierd to see this type of assignment) One more doubt is : Is parallel assignment an operator?? Thanks

    Read the article

  • How do I make Geany my default editor on Ubuntu?

    - by Programming Noob
    I actually want to change the default text editor on my Ubuntu 12.04 from nano to Geany. When I used this code: update-alternatives --config editor .. I don't see Geany in the list. So to add Geany, this is supposed to work right? update-alternatives --install /usr/bin/geany geany /usr/bin/geany 10 Also, on a side note, can you tell me if you would personally suggest me to change the default editor from nano to Geany, and why?

    Read the article

  • Which programming language to get into?

    - by user602479
    I'm ending my third term in a few weeks so I have some spare time coming up. I'd like to spend it seriously digging into programming. My problem: I'm not sure which language to begin with. Just to be clear, I don't want to start a language-y-compared-to-language-z discussion. There are a some other issues that play a major role. In my 5th term I'm going to be participating in a major practical course which will include either Java or C programming. It will take a lot of time and energy, as I found out while talking to a few students who passed the final exams (only 15% pass on their first try). Which practical course I will take is randomly decided. My skills so far are the absolute basics of Java and C programming. I know the different data types and how to handle them, objects, pointers, thread programming, etc. All of that is on a very low level, though. My question now is, what language should I start seriously practicing? Java: I did my first GUIs with this language. I'm familiar with Eclipse but I need a project to work on (which I don't have) to really keep me pushing. Besides that, I don't think it would help me if I have to do C in a year. C: As with Java, I can't think of a personal project to keep me working and keep me interested in programming. If I get assigned to Java in a year, this wouldn't give me any advantages either, would it? (No objects, etc.) Objective-C: I recently came up with this idea. I have a Mac; I'm not really familiar with Xcode but I have one or two personal projects I'd like to work on. Further, I would be working with objects (as in Java) and C language constructs which would both be great for this practical course in a year. What do you think I should begin with? Should I just stick to Java and hope for the best, force myself through C or start (nearly) completely from the beginning with Objective C? Maybe you folks could give me some good advice that would stop me from switching from one language to the next?

    Read the article

  • How to approach parallel processing of messages?

    - by Dan
    I am redesigning the messaging system for my app to use intel threading building blocks and am stumped trying to decide between two possible approaches. Basically, I have a sequence of message objects and for each message type, a sequence of handlers. For each message object, I apply each handler registered for that message objects type. The sequential version would be something like this (pseudocode): for each message in message_sequence <- SEQUENTIAL for each handler in (handler_table for message.type) apply handler to message <- SEQUENTIAL The first approach which I am considering processes the message objects in turn (sequentially) and applies the handlers concurrently. Pros: predictable ordering of messages (ie, we are guaranteed a FIFO processing order) (potentially) lower latency of processing each message Cons: more processing resources available than handlers for a single message type (bad parallelization) bad use of processor cache since message objects need to be copied for each handler to use large overhead for small handlers The pseudocode of this approach would be as follows: for each message in message_sequence <- SEQUENTIAL parallel_for each handler in (handler_table for message.type) apply handler to message <- PARALLEL The second approach is to process the messages in parallel and apply the handlers to each message sequentially. Pros: better use of processor cache (keeps the message object local to all handlers which will use it) small handlers don't impose as much overhead (as long as there are other handlers also to be run) more messages are expected than there are handlers, so the potential for parallelism is greater Cons: Unpredictable ordering - if message A is sent before message B, they may both be processed at the same time, or B may finish processing before all of A's handlers are finished (order is non-deterministic) The pseudocode is as follows: parallel_for each message in message_sequence <- PARALLEL for each handler in (handler_table for message.type) apply handler to message <- SEQUENTIAL The second approach has more advantages than the first, but non-deterministic ordering is a big disadvantage.. Which approach would you choose and why? Are there any other approaches I should consider (besides the obvious third approach: parallel messages and parallel handlers, which has the disadvantages of both and no real redeeming factors as far as I can tell)? Thanks!

    Read the article

  • Imperative vs. component based programming [closed]

    - by AlexW
    I've been thinking about how programming and more specifically the teaching of programming is advocated amongst the community (online). Often I've heard that Ruby and RoR is an ideal platform for learning to program. I completely disagree... RoR and Ruby are based on the application of the component based paradigm, which means they are ideal for rapid application development. This is much like the MVC model in PHP and ASP.NET But, learning a proper imperative language like Java or C/C++ (or even Perl and PHP) is the only way for a new programmer to explore logic itself, and not get too bogged down in architectural concerns like the need for separation of concerns, and the preference for components. Maybe it's a personal preference thing. I rather think that the most interesting aspects to programming are the procedural bits of code I write that actually do stuff rather than the project planning, and modelling that comes about from fully object oriented engineering or simply using the MVC model. I know this may sound confused to some of you. I feel strongly though that the best way for programming to be taught is through imperative and procedural methods. Architectural (component) methods come later, if at all. After all, none of the amazing algorithms that exist were based on OOP practice! It's all procedural code when it comes to the 'magic'. OOP is useful in creating products and utilities. Algorithms are what makes things happen, and move data around, and so imperative (and/or procedural) code are what matters most. When I see programmers recommending Ruby on Rails to newbie developers, I think it's just so wrong. Just because you write less code with Ruby does not make it easier to do! It's the opposite... you have to know loads more to appreciate its succinct nature. New coders who really want to understand the nuts and bolts of coding need to go away and figure out writing methods/functions (i.e. imperative programming) and working in procedural style, in order to grasp the fundamentals, first, before looking into architectural ways of working. So, my question is: should Ruby ever be recommended as a first language? I think no (obviously)... what arguments are there for it?

    Read the article

  • Networked Parallel Port in Linux / KVM / QEMU

    - by korkman
    What I want to use is the "-parallel" tcp or udp option from KVM / QEMU, but I don't seem to find any server for this client. I don't serve a printer but a hardware dongle. I checked ser2net, which does provide "/dev/lp0" sharing, but it doesn't seem to work for KVM / QEMU. I suspect KVM / QEMU requires "/dev/parport0". I did rmmod lp, modprobe ppdev, linked ser2net to parport0, but it didn't work out. Perhaps ser2net is not suited for this. I tried socat as well, and I tried netcat. No success. Does anyone know any KVM / QEMU compatible parallel port server? Or did any of netcat, socat or ser2net work for you?

    Read the article

  • Parallel prologue and epilogue in Grid Engine

    - by ajdecon
    We have a cluster being used to run MPI jobs for a customer. Previously this cluster used Torque as the scheduler, but we are transitioning to Grid Engine 6.2u5 (for some other features). Unfortunately, we are having trouble duplicating some of our maintenance scripts in the Grid Engine environment. In Torque, we have a prologue.parallel script which is used to carry out an automated health-check on the node. If this script returns a fail condition, Torque will helpfully offline the node and re-queue the job to use a different group of nodes. In Grid Engine, however, the queue "prolog" only runs on the head node of the job. We can manually run our prologue script from the startmpi.sh initialization script, for the mpi parallel environment; but I can't figure out how to detect a fail condition and carry out the same "mark offline and requeue" procedure. Any suggestions?

    Read the article

  • Programming languages with a Lisp-like syntax extension mechanism

    - by Giorgio
    I have only a limited knowledge of Lisp (trying to learn a bit in my free time) but as far as I understand Lisp macros allow to introduce new language constructs and syntax by describing them in Lisp itself. This means that a new construct can be added as a library, without changing the Lisp compiler / interpreter. This approach is very different from that of other programming languages. E.g., if I wanted to extend Pascal with a new kind of loop or some particular idiom I would have to extend the syntax and semantics of the language and then implement that new feature in the compiler. Are there other programming languages outside the Lisp family (i.e. apart from Common Lisp, Scheme, Clojure (?), Racket (?), etc) that offer a similar possibility to extend the language within the language itself? EDIT Please, avoid extended discussion and be specific in your answers. Instead of a long list of programming languages that can be extended in some way or another, I would like to understand from a conceptual point of view what is specific to Lisp macros as an extension mechanism, and which non-Lisp programming languages offer some concept that is close to them.

    Read the article

  • Do you think that exposure to BASIC can mutilate your mind? [closed]

    - by bigown
    It is practically impossible to teach good programming to students that have had a prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration -- Edsger W. Dijkstra I have deep respect to Dijkstra but I don't agree with everything he said/wrote. I disagree specially with this quote on linked paper wrote 35 years ago about the Dartmouth BASIC implementation. Many of my coworkers or friends programmers started with BASIC, questions below have answers that indicate many programmers had their first experience on programming at BASIC. AFAIK many good programmers started at BASIC programming. I'm not talking about Visual Basic or other "modern" dialects of BASIC running on machines full of resources. I'm talking about old times BASIC running on "toy" computer, that the programmer had to worry about saving small numbers that need not be calculated as a string to save a measly byte because the computer had only a few hundreds of them, or have to use computed goto for lack of a more powerful feature, and many other things which require the programmer to think much before doing something and forcing the programmer to be creative. If you had experience with old time BASIC on a machine with limited resources (have in mind that a simple micro-controller today has much more resources than a computer in 1975, do you think that BASIC help your mind to find better solutions, to think like an engineer or BASIC drag you to dark side of programming and mutilated you mentally? Is good to learn a programming language running on a computer full of resources where the novice programmer can do all wrong and the program runs without big problems? Or is it better to learn where the programmer can't go wrong? What can you say about the BASIC have helped you to be a better/worse programmer? Would you teach old BASIC running on a 2KB (virtual) machine to a coming programmer? Sure, only exposure to BASIC is bad. Maybe you share my opinion that modern BASIC doesn't help too much because modern BASIC, as long other programming languages, gives facilities which allow the programmer doesn't think deeper. Additional information: Why BASIC?

    Read the article

  • Extending Programming Languages

    - by chpwn
    (Since I just posted this in another question, but my browser had to be annoying and submit it without content first, here it is again:) I'm a fan of clean code. I like my languages to be able to express what I'm trying to do, but I like the syntax to mirror that too. For example, I work on a lot of programs in Objective-C for jailbroken iPhones, which patch other code using the method_setImplementation() function of the runtime. Or, in pyobjc, I have to use the syntax UIView.initWithFrame_(), which is also pretty awful and unreadable with the way the method names are structured. In both cases, the language does not support this in syntax. I've found three basic ways that this is done: Insane macros. Take a look at this "CaptainHook", it does what I'm looking for in a usable way, but it isn't quite clean and is a major hack. There's also "Logos", which implements a very nice syntax, but is written in Perl parsing my code with a ton of regular expressions. This scares me. I like the idea of adding a %hook ClassName, but not by using regular expressions to parse C or Objective-C. Finally, there is Cycript. This is an extension to JavaScript which interfaces with the Objective-C runtime and allows you to use Objective-C style code in your JavaScript, and inject that into other processes. This is likely the cleanest as it actually uses a parser for the JavaScript, but I'm not a huge fan of that language in general. Basically, this is a two part question. Should, and how should, I create an extension to Python and Objective-C to allow me to do this? Is it worth writing a parser for my language to transform the syntax into something nicer, if it is only in a very specialized niche like this? Should I just live with the horrible syntax of the default Objective-C hooking or pyobjc?

    Read the article

  • How to escape % in roxygen literate programming?

    - by Karsten W.
    The default value of a parameter of my function contains a "%". This seems to be a problem for roxygen, it produces a lot of warnings and R CMD check fails when trying to build latex documentation. How can I make this function (and its documentation) work? Using %% or \% instead of % does not help. #' Test escape \% from in-source documentation (roxygen). #' #' What happens when parameters contain special latex characters? #' #' @param x unsuspicious parameter #' @param format sprintf format string (default "\%5.0f") #' #' @return formatted string #' @export #' @author Karsten Weinert testroxy <- function(x, format = "%5.0f") { sprintf(format,x) }

    Read the article

  • Please give the solution of the following programs in R Programming

    - by NEETHU
    Table below gives data concerning the performance of 28 national football league teams in 1976.It is suspected that the no. of yards gained rushing by opponents(x8) has an effect on the no. of games won by a team(y) (a)Fit a simple linear regression model relating games won by y to yards gained rushing by opponents x8. (b)Construct the analysis of variance table and test for significance of regression. (c)Find a 95% CI on the slope. (d)What percent of the total variability in y is explained by this model. (e)Find a 95% CI on the mean number of games won in opponents yards rushing is limited to 2000 yards. Team y x8 1 10 2205 2 11 2096 3 11 1847 4 13 1803 5 10 1457 6 11 1848 7 10 1564 8 11 1821 9 4 2577 10 2 2476 11 7 1984 12 10 1917 13 9 1761 14 9 1709 15 6 1901 16 5 2288 17 5 2072 18 5 2861 19 6 2411 20 4 2289 21 3 2203 22 3 2592 23 4 2053 24 10 1979 25 6 2048 26 8 1786 27 2 2876 28 0 2560 Suppose we would like to use the model developed in problem 1 to predict the no. of games a team will win if it can limit opponents yards rushing to 1800 yards. Find a point estimate of the no. of games won when x8=1800.Find a 905 prediction interval on the no. of games won. The purity of Oxygen produced by a fractionation process is thought to be percentage of Hydrocarbon in the main condenser of the processing unit .20 samples are shown below. Purity(%) Hydrocarbon(%) 86.91 1.02 89.85 1.11 90.28 1.43 86.34 1.11 92.58 1.01 87.33 0.95 86.29 1.11 91.86 0.87 95.61 1.43 89.86 1.02 96.73 1.46 99.42 1.55 98.66 1.55 96.07 1.55 93.65 1.4 87.31 1.15 95 1.01 96.85 0.99 85.2 0.95 90.56 0.98 (a)Fit a simple linear regression model to the data. (b)Test the hypothesis H0:ß=0 (c)Calculate R2 . (d)Find a 95% CI on the slope. (e)Find a 95% CI on the mean purity and the Hydrocarbon % is 1. Consider the Oxygen plant data in Problem3 and assume that purity and Hydrocarbon percentage are jointly normally distributed r.vs (a)What is the correlation between Oxygen purity and Hydrocarbon% (b)Test the hypothesis that ?=0. (c)Construct a 95% CI for ?.

    Read the article

  • Programming language shootout: code most like pseudocode for Dijkstra's Algorithm

    - by Casebash
    Okay, so this question here asked which language is most like executable pseudocode, so why not find out by actually writing some code! Here we have a competition where I will award a 100 point bounty (I know its not much, but I am poor after the recalc) to the code which most resembles this pseudocode. I've read through this a few times so I'm pretty sure that this pseudocode below is correct and about as unambiguous as pseudocode can be. Personally, I'm going to have a go in Python and probably Haskell as well, but I'm just learning the later so my attempt will probably be pretty poor. Note: Obviously to implement anything looking like this you'll have to define quite a few library functions. define DirectedGraph G with: Vertices as V, Edges as E define Vertex A, Z declare each e in E as having properties: Boolean fixed with: initial=false Real minSoFar with: initial=0 for A else infinity define PriorityQueue pq with: objects=V initial=A priority v=v.minSoFar create triggers for v in V: when v.minSoFar event reduced then pq.addOrUpdate v when v.fixed event becomesTrue then pq.remove v Repeat until Z.fixed==True: define Vertex U=pq.pop() U.fixed=True for Edge E adjacentTo U with other Vertex V: V.minSoFar=U.minSoFar+length(E) if reducesValue return Z.name, Z.minSoFar

    Read the article

  • C#.NET Socket Programming: Connecting to remote computers.

    - by Gio Borje
    I have a typical server in my end and a friend using a client to connect to my IP/Port and he consistently receives the exception: "A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond {MY_IP}:{MY_PORT}"—You don't need to know my IP. The client and server, however, work fine on the loopback address (127.0.0.1). I also do not have any firewall nor is windows firewall active. Server: static void Main(string[] args) { Console.Title = "Socket Server"; Console.WriteLine("Listening for messages..."); Socket serverSock = new Socket( AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); IPAddress serverIP = IPAddress.Any; IPEndPoint serverEP = new IPEndPoint(serverIP, 33367); SocketPermission perm = new SocketPermission(NetworkAccess.Accept, TransportType.Tcp, "98.112.235.18", 33367); serverSock.Bind(serverEP); serverSock.Listen(10); while (true) { Socket connection = serverSock.Accept(); Byte[] serverBuffer = new Byte[8]; String message = String.Empty; while (connection.Available > 0) { int bytes = connection.Receive( serverBuffer, serverBuffer.Length, 0); message += Encoding.UTF8.GetString( serverBuffer, 0, bytes); } Console.WriteLine(message); connection.Close(); } } Client: static void Main(string[] args) { // Design the client a bit Console.Title = "Socket Client"; Console.Write("Enter the IP of the server: "); IPAddress clientIP = IPAddress.Parse(Console.ReadLine()); String message = String.Empty; while (true) { Console.Write("Enter the message to send: "); // The messsage to send message = Console.ReadLine(); IPEndPoint clientEP = new IPEndPoint(clientIP, 33367); // Setup the socket Socket clientSock = new Socket( AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); // Attempt to establish a connection to the server Console.Write("Establishing connection to the server... "); try { clientSock.Connect(clientEP); // Send the message clientSock.Send(Encoding.UTF8.GetBytes(message)); clientSock.Shutdown(SocketShutdown.Both); clientSock.Close(); Console.Write("Message sent successfully.\n\n"); } catch (Exception ex) { Console.WriteLine(ex.Message); } } }

    Read the article

< Previous Page | 31 32 33 34 35 36 37 38 39 40 41 42  | Next Page >