Questions on parallel computing in Mathematica.

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2
votes
2answers
31 views

Disappearing variable in parallel computations

I have a problem with parallel computations. When I try to evaluate formula like this: Do[m[i]=2,{i,1,10}] and then I try to call for instance ...
3
votes
0answers
52 views

Launching 49+ local kernels fails in 10.0.2 [on hold]

I do large-ish parallel computations in Mathematica on quad socket 16 core nodes (64 physical cores). In version 8.x, LaunchKernels[64] works reliably. In version 10.0.2, LaunchKernels[48] works ...
0
votes
0answers
30 views

Side effects in ParallelDo

I am trying to import many different matrices saved as separate .MX files in one bix matrix. When I used ...
3
votes
1answer
81 views

Parallel Apply on a deeply nested expression

I have a deeply nested expression, i.e. something like {{{{...}..}..}..}, and I'd like to use Apply in a parallel fashion, e.g. ...
2
votes
1answer
37 views

Dynamic Output during ParallelMap

I can't seem to figure out how to dynamically output a variable that is being used in a parallel evaluation. Below is an example function that demonstrates my problem. ...
1
vote
0answers
56 views

Avoid copying memory for each subkernel

Here is a simplified example illustrating my issue; ...
0
votes
0answers
50 views

Appending elements to a list in parallel table

Is there any way to store values in a list that is being computed in parallel? For example, if ParallelTable is computing some ...
0
votes
1answer
40 views

How to set a shared variable Power (a modified one)?

Unprotect[Power]; Power[0|0., 0|0.] = 1 ; Protect[Power]; Table[0^0, {i, 5}] No problem at all. ParallelTable[0^0, {i, 5}] ...
2
votes
1answer
46 views

Problem with ParallelTable

The following code creates an array of length N, such that the sum of elements is less than or equal to p and each element is between 0 and l. All elements are integers. (code courtesy, Kellen Myers ...
3
votes
1answer
56 views

Why doesn't my expression evaluate at the subkernel?

Consider this code: ...
2
votes
1answer
55 views

How to access directly the “CUDA Memory” address from another parallel kernel?

I work with CUDALink and have some small successes. I use direct calculation on GPU without using CPU (only for sanding commands for CUDA function). Until now I have stored on the hard drive with ...
4
votes
1answer
117 views

Definitions are not distributed to parallel kernels

I have a small package with utilities, which looks like that: ...
0
votes
0answers
44 views

How many CPUs does gridMathematica support?

In the features section it is written that: gridMathematica is an integrated extension system for increasing the power of your Mathematica licenses. gridMathematica Server gives Mathematica users ...
2
votes
1answer
72 views
1
vote
1answer
64 views

Why does Mathematica Spawn Additional Dock Icons on OS X?

I've been running a calculation in parallel that requires a rasterize, and doing this requires one to wrap the rasterization with a UsingFrontEnd command (as is ...
2
votes
0answers
56 views

What was the thought behind the parallel versions of Table, Map, etc..?

There separately named versions of the parallel analogues of Map[] and friends: ...
2
votes
1answer
68 views

Intensive test parallel computation?

I need an example of a not-too-complicated yet intensive parallel computation in Mathematica. The result of the computation should be known before hand. I need this to test the capabilities of a ...
1
vote
2answers
62 views

Incomplete Parallel Mapping

I am still struggling on how to nicely handle list operations in Mathematica, and perform simultaneously parallel computation. We consider a tab of the form ...
1
vote
0answers
77 views

Can GPU (CUDA) speed up LinearSolve?

Is there a way to use GPU (CUDA) to speed up LinearSolve?
2
votes
2answers
55 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
201 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
50 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
101 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 ...
2
votes
0answers
72 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
36 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
votes
0answers
31 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 ...
8
votes
1answer
103 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 ...
1
vote
0answers
46 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
vote
0answers
35 views

Evaluation is finished but local kernel still works [closed]

I am executing complex independent calculations of the same type in parallel. ...
1
vote
1answer
46 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
44 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
121 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 ...
3
votes
1answer
72 views
4
votes
2answers
87 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 ...
1
vote
0answers
76 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: ...
3
votes
0answers
46 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
30 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 ...
1
vote
0answers
47 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
votes
1answer
52 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: ...
2
votes
0answers
67 views

ParallelTable kernels die - maybe Mathlink 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
62 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
1answer
106 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 ...
0
votes
1answer
68 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: ...
3
votes
1answer
111 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
98 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
vote
0answers
48 views

Troubles with ParallelEvaluate

I need to evaluate the same expression on all subkernels just like ParallelEvaluate does. This code distributes perfectly (2 kernels): ...
1
vote
1answer
153 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 ...
2
votes
2answers
289 views

Will Parallelize in this programme help it run faster? [closed]

I have a programme, and inside it this line of code. ...
0
votes
1answer
173 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
58 views

Parallelization and evaluation of random number generation

Suppose I have the following functions: ...