Questions on parallel computing in Mathematica.

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0
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1answer
49 views

ParallelTable and global variables

I want to calculate the convolution of two function. In order to generate variables automatically, I use such an expressions: ...
8
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1answer
90 views

Setting up tunnel to access compute nodes behind private LAN via front-end

Context I find the front end on macos way more convenient and I would like to keep my notebooks on my macbook. On the other hand, I have access faster multi-core linux machines behind a LAN. Hence I ...
0
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2answers
32 views

How to share numbered variables between kernels

Supose I have two variables v[1] and v[2]. I used: SetSharedVariable[{v[1], v[2]}] Then, ...
5
votes
1answer
187 views

Listable vs Parallel

Are listability and being parallelized the same? In other words, Does parallelizing a listable function which has already a list as of its argument make the computation faster? In the documentation ...
4
votes
0answers
49 views

The change of precision doesn't work in ParallelDo. Is it a bug in Parallel?

Cross-post: http://zhidao.baidu.com/question/2075301703219376588.html Input: ...
2
votes
1answer
87 views

How to parallelize the most outer loop only?

I have two Doloops. The outer loop iterate over the inner loop. The inner loop contains a set of step by step instructions which each next step depends on the ...
1
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0answers
51 views

Bug in parallel computing

The following is a simplified example. We construct a library function f and another library function g, in which the library function f is called. ...
1
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0answers
25 views

Parallel Kernel Status

For parallel computing, the window Parallel Kernel Status shows some information on the subkernels. I can use two kernels, and which each of them I can do parallel computations. However, it seems that ...
0
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0answers
26 views

Parallel assigning to an Association

This is a simplified example of a problem I ran into. I want to count how often a subkernel executes a given computation. So, after having launched the subkernels, I construct an association with ...
1
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0answers
38 views

Problem with ParallelTable in using externaly defined iterator [closed]

In order to reduce my computation time, I'm making some tests with parallel computation, especially with ParallelTable. Here is a simple code : ...
1
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0answers
32 views

Evaluation is finished but local kernel still works [closed]

I am executing complex independent calculations of the same type in parallel. ...
1
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0answers
59 views

What does this Java error mean? Why is it raised?

I want to launch some kernels on a cluster that uses SGE. The server's operating system is Linux Cent-OS. According to Mathematica documentation, I've added these commands inside my code: ...
1
vote
1answer
42 views

Global variales, Paralell computation and Limiting notebook's contex

If I limit the context of each notebook: and use parallel computation: ParallelTable[ToExpression["b" <> ToString[j]], {j, 1, 10}] then after ...
2
votes
1answer
35 views

Lightweight Grid saving to file

I'm trying to launching my first jobs on LightWeight Grid using ParallelDo. I have 10000 jobs, each of which returns a 1M output, which I would like saved to a file on the head machine, one file per ...
3
votes
0answers
80 views

Mathematica + RasPi + Parallela = Kaboom?

Is it possible to use the Parallela computing platform to enhance Mathematica computing on a Raspberry Pi? It's not at all clear to me how to interface the two boards (here it says it's done via ...
4
votes
2answers
80 views

How to use multicore in this case?

Say I have something like this: myfun[dataA,X1,Y1,Z1,W1]; myfun[dataB,X2,Y2,Z2]; myfun[dataC,X3,Y3,Z3]; (* with many more of the same *) Each would take about 5 ...
3
votes
0answers
42 views

Parallelization and memoization? [duplicate]

I have an expensive function on discrete values, f[n_] := f[n] = n^2 (* Expensive calculation *) Since f[n] is an expensive ...
0
votes
0answers
24 views

Symbol definition in parallel kernels

Suppose I have a reasonably large number of floating point arrays, obtained from prior numerical simulations. These are stored as binary files named data_#####.dat ...
2
votes
1answer
45 views

Button action preventing parallel execution?

I couldn't find a better title, so I'll jump straight to the example! There is this long list of slow jobs to be executed in a parallel way, at the press of a button: ...
1
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0answers
41 views

Symbolic Nullspace computation in parallel

I am trying to determine the nullspace of a large symbolic matrix. The single core evolution seems to take too long. I tried Parallelize[] on the commands ...
2
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0answers
30 views

ParallelTable kernels die - maybe Matlink timeout?

I am new to parallel computing in Mathematica. I am using LaunchKernels[16] ParallelTable[] to parallelize calculations. The ParallelTable consists of approx ...
0
votes
1answer
48 views

ParallelDo and distributing function definition

Consider this code: f[i_] := Sin[i] Do[array1[i] = f[i], {i, 1, 5}] Table[array1[i], {i, 1, 5}] Returns: ...
4
votes
0answers
67 views

Eigensystem on HPC

I am submitting Mathematica jobs to an HPC. I have a large matrix that is a function of (x,y) and I am diagonalizing it for around 500 points in the plane. My initial idea was to request a node with ...
1
vote
1answer
94 views

Remote Kernel Setup: SSH fails with exit code 32512

I am having trouble with configuring parallel kernels. What I want to do is the following: run remote kernels on my home server to which I would like to connect from work using my laptop. Both ...
3
votes
1answer
89 views

Image background subtraction using parallel computing

I am developing a program for pattern recognition. I want to use the parallel computing to get a real time application. I have two cameras where each one gives n frames/second. I need to process the ...
5
votes
2answers
96 views

Paralleizing the Plot function internally

I have a function of several parameters, funct(a,b,c,d,f,...). Mathematica deals with this function fine but it takes a minute or so to make a data point. I want to plot graphs of funct using code ...
1
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0answers
46 views

Troubles with ParallelEvaluate

I need to evaluate the same expression on all subkernels just like ParallelEvaluate does. This code distributes perfectly (2 kernels): ...
2
votes
2answers
286 views
-1
votes
1answer
120 views

How to use multiple core in evaluation?

Sorry if the question is very basic, that's because I am newbie in the Mathematica. Assume I have a module that is supposed to do a very very long calculation result = Table[0, {i, 100000000}]; ...
2
votes
1answer
52 views
2
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0answers
27 views

do successive parallel computations require distribute definitions at each intermediate step?

Suppose I am doing a parallel computation, say, using parallel table. I distribute necessary definitions to all kernels. After computation is done, I would like to use the first result in another ...
3
votes
1answer
101 views

Using ParallelMap to run multiple Game of Life simulations simultaniously

My Assignment and Code As an exercise in Parallel computing I've been tasked with implementing Conway's GoL in a way such that at every iteration only a fraction of cells are updated. I'm then to run ...
1
vote
1answer
129 views

Parallel numerically integrated function can't be plotted [closed]

I've been working on a problem where I need to integrate a function numerically. The function is quite complex and it takes almost an hour for Mathematica to make a plot. To speed the process up I ...
2
votes
0answers
50 views

k-means clustering in parallel

How can the k-means algorithm for some given distance function be implemented using ParallelMap or other parallel processing program constructs in Mathematica?
1
vote
0answers
83 views

Why does ParallelTable give different answer than Table [closed]

Consider the following code a0 = 6.; ls1 = ParallelTable[k, {k, -π/a0, π/a0, π/a0/100}]; ls2 = Table[k, {k, -π/a0, π/a0, π/a0/100}]; ls1 == ls2 (*False*) Why ...
1
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0answers
60 views

NMaximize stops evaluating my function when run in parallel

I am trying to maximize the results of a Monte Carlo simulation with respect to some input variables. ...
3
votes
1answer
147 views

Parallel kernel and front end

I have a piece of code which looks like this: ParallelTable[ Monitor[ Table[ <code here> ,{i,i1,i2]; ,i]; ] so basically a ...
4
votes
1answer
71 views

Parallelizing sparse array construction

I have a very large sparse array, and the computation of individual matrix elements is fairly expensive. The Matrix is Hermitian and traceless, so I would like to construct only the sub-diagonal ...
6
votes
1answer
299 views

Optimizing Monte Carlo simulation of a Pred-Prey model

My assignment and code As part of an assignment for one of my classes, I'm trying to run a "massive" Monte Carlo simulation in Parallel on the follow model: ...
1
vote
1answer
77 views

Connect to Windows kernel from Linux computer

I've seen many questions regarding the connection to a Linux machine from a Windows one, but I need to do the opposite. Situation: I have Mathematica on my Linux laptop (...
3
votes
1answer
183 views

Issue in ParallelTable after evaluating another function using NDSolve and FindRoot. What is wrong with this inverse?

I am trying to find the inverse of a function which is defined through NDSolve and NIntegrate. The question is pretty similar ...
3
votes
0answers
144 views

OpenCL vs. CUDA with Mathematica

I am thinking about using GPU programming with Mathematica using a MacBook Pro with a NVIDIA GPU. At this page, the Mathematica documentation says "Programming OpenCL in the Wolfram Language is simple ...
6
votes
2answers
133 views

Communication between local kernels

this is my first post but you have already helped me so many times that I have to start by saying thanks a lot! I have a really long calculation to do, and I have used the Evaluation->Kernel ...
1
vote
0answers
43 views

Placing package in existing Utilities` context has odd paraellelization effect

I noticed this in V.10 but possibly it was in effect in V.9. I have a package which in simplified form looks like:- ...
24
votes
1answer
775 views

Mma 10: Half the parallel power (Macs)?

Here is a comparison of the parallel kernels launched under Mathematica under v9 and v10, on the same identical current 2014 R2-D2 Mac Pro ... [ Update: Valerio has commented that the same issue ...
0
votes
1answer
86 views

ParallelMap returns incorrect results over Map

I've written a function to pull in the useful column of a large data file: ...
7
votes
0answers
169 views

Partial Differential Equation in Parallel

is there any native way to implement multi-core parallel solving of PDE in Wolfram Mathematica? WM 10 now supports Finite Elements Method, but it is actually useless without parallelization. Usually ...
2
votes
0answers
184 views

ParallelSum in Mathematica 9 vs 10

Here's part of a package I'm working on: ...
0
votes
0answers
80 views

strange timing behavior

The following code is from a book about Mathematica. ...