Questions on parallel computing in Mathematica.

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3
votes
1answer
122 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
57 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
84 views

Avoid copying memory for each subkernel

Here is a simplified example illustrating my issue; ...
1
vote
1answer
120 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
43 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
84 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
72 views

Why doesn't my expression evaluate at the subkernel?

Consider this code: ...
2
votes
1answer
86 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
158 views

Definitions are not distributed to parallel kernels

I have a small package with utilities, which looks like that: ...
0
votes
0answers
70 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
80 views
1
vote
1answer
81 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
67 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
84 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
67 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
151 views

Can GPU (CUDA) speed up LinearSolve?

Is there a way to use GPU (CUDA) to speed up LinearSolve?
2
votes
2answers
80 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
219 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 ...
5
votes
0answers
56 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
134 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
105 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. ...
2
votes
0answers
91 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
38 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
110 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
52 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
40 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
51 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
58 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 ...
4
votes
0answers
228 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
75 views
4
votes
2answers
119 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
120 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
48 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
37 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
76 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
64 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
119 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
76 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
122 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
125 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
138 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
111 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
55 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
1answer
321 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
299 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
361 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
66 views

Parallelization and evaluation of random number generation

Suppose I have the following functions: ...
2
votes
0answers
36 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
0answers
76 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?
3
votes
1answer
134 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 ...