Questions on parallel computing in Mathematica.

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2
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1answer
252 views

Clearing distributed definitions from remote kernels

The documentation shows the following example to "Remove a distributed definition..." Oh, course this doesn't work without redefining the function prior to re distributing the definition. The ...
2
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1answer
75 views
2
votes
1answer
123 views

ParallelTable slowdown for a task involving ComponentMeasurements

I'm having trouble understanding a slowdown associated with code I'm running, which should be trivial to parallelize. My code looks something like this: ...
2
votes
1answer
40 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. ...
2
votes
1answer
57 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
2answers
164 views

Definitions inside ParallelTable?

How can I make definitions inside ParallelTable to use them outside? For example, if I execute: ...
2
votes
2answers
161 views

Executing several input cell simultaneously with parallelization

How can I execute more than one input cell simultaneously using different processor. For example consider this two cells ...
2
votes
1answer
221 views

How to parallel this nested table efficiently?

I have an 8 core CPU and want to parallel evaluate the following nested Table Table[Table[expr[i,j], {i,1,10}], {j,1,4}] But ...
2
votes
1answer
247 views

How can I prevent these warnings while using ParallelTable

I have this code to find all the permutations of a set of letters that form legal words. ...
2
votes
1answer
112 views

Parallel computing NInverseFourierTransForm

I am running the code below, and it works perfectly. I have some function in Fourier space, and I take the numerical InverseFourierTransform. However, I will have ...
2
votes
1answer
67 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 ...
2
votes
1answer
71 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 ...
2
votes
1answer
112 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
1answer
53 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 ...
2
votes
1answer
208 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
1answer
63 views

Parallelization and evaluation of random number generation

Suppose I have the following functions: ...
2
votes
1answer
130 views

SSH known hosts in Windows (Error code = 124)

I had to re-install Raspbian OS and now it has new SSH key. SSH clients usually let ignore this fact and save the new key, but not now. Mathematica gives no way to go if the Host Key was changed. I ...
2
votes
1answer
183 views

Server running WolframLightWeightGrid manager loses licensing information

"Once more into the breach..," I have 2 identical Xserves running OS X Server 10.6.8 each with 2 quad core Intel Xenon processors a total of 16 kernels. I have configured both servers identically ...
2
votes
1answer
239 views

how to nest parallelized computations on a cluster?

I am lucky to have access to a computational cluster and I could submit my job to many-many cores. As I need to evaluate a numerical integral within a numerical integral, I would like to know if I can ...
2
votes
0answers
18 views

ParallelSubmit and WaitNext: check if a job is done before calling WaitNext

Say I process something with ParallelSubmit: LaunchKernels[] job = ParallelSubmit[1 + 2] Parallel`Developer`QueueRun[] Then, I will use ...
2
votes
0answers
57 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
0answers
87 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
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0answers
58 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 ...
2
votes
0answers
84 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 ...
2
votes
0answers
33 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 ...
2
votes
0answers
238 views

ParallelSum in Mathematica 9 vs 10

Here's part of a package I'm working on: ...
2
votes
0answers
161 views

Death of parallel sub-kernels

EDIT : Finally, the new Mathematica 10.0 seems to fix it. I have a little parallelization problem. I wrote a code to generate a quasicrystal by dynamical generation. Here the code: ...
2
votes
0answers
45 views

Timing of ParallelDo versus Do: simple example [duplicate]

I'm trying to understand why a simple do-loop takes substantially longer when done in parallel than sequentially: ...
2
votes
0answers
101 views

ParallelTable and expensive functions

I would like to build up a 2D-Table using ParallelTable as follows ...
2
votes
0answers
321 views

Remote kernel shuts down after several seconds

I have Mathematica 9 installed on two Windows Server 2008 R2 machines. Now i want to try using one of them as a frontend with local kernels and the other one for remote kernels. OpenSSH 6.5 for ...
2
votes
0answers
109 views

Whether NIntegrate evaluation is multithreaded or not?

About MultiThread evaluation I am talking about here, see this post I am NIntegrate the function grarm[e, 3, dimension, 1, 1, 0.005]. There is matrix operation in ...
2
votes
0answers
71 views

Setting Up Lightweight Grid On Multiple Clients Programmatically

I have a number of computers which all might need to use the same (client) configuration for the Wolfram Lightweight Grid at some point. I know that there are ways to programmatically set certain ...
2
votes
0answers
86 views

How can you link Parallel Mapping and Error tracking

Following this question and the comments made, together with the information in this question, the following code allows error tracking and debugging very nicely. ...
2
votes
0answers
132 views

correct usage of ParallelTable

I am trying to parallelize my script. Here is a MWE of how I have done it: ...
2
votes
1answer
155 views

Mathematica 9.0 problem: ParallelTable with SQLExecute

I have run into the following problem: when I try to run the following code in Mathematica 9 I get SQL connection error on all kernels. The code is: ...
1
vote
3answers
128 views

Where Statement

Is there a "parallel" way to perform these operations? Indices = {} For[i = 1, i <= Length[w], i++, If[w[[i]] < 0, AppendTo[Indices, i]]] Which gives a ...
1
vote
2answers
43 views

Limit the number of processors used by ParallelTable?

By default, ParallelTable will use all the processors available in a PC. Is there a way to set a limit to the number of processors used by ...
1
vote
2answers
63 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
1answer
341 views

Suppress warnings in ParallelTable

I'm using ParallelTable to evaluate a function that involves NIntegrate. There are a lot of ...
1
vote
2answers
524 views

Integration and Parallel Computing in Mathematica

In mathematica, how would I use parallel computing (or paralleltable) to compute the integrals of $x^2$, $x$, $3x$ from $x=0$ to $10$ just like in the first answer of ...
1
vote
1answer
204 views

ParallelTable and DistributeDefinitions

I have a function in the following form: function[...] := With[ {...}, Table[ anotherfunction[i, j, ...], {i, ...}, {j, ...}, ... ] ] If ...
1
vote
1answer
74 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 ...
1
vote
1answer
130 views

ParallelTable of ParametricNDSolve objects fail

There seems to be a problem with ParametricNDSolveValue togeteher with ParallelTable First we create a ParametricNDSolveValue object ...
1
vote
1answer
230 views

Version differences in Parallelize

I am having a problem which I guess is due to version difference. I have to generate a list of unitary matrices, which I can do easily. However I came to know about ...
1
vote
1answer
78 views

DSolve for a huge linear inhomogeneous ODE in parallel

I have a linear inhomogeneous ODE with constant coefficients, which I need to solve symbolically. The problem is that the inhomogeneity is sum of more than 100 terms (however, each term itself is ...
1
vote
1answer
46 views

Changing a Part of a variable within ParallelDo

I want to evaluate nested do as a parallel computations. My formula looks like: ...
1
vote
1answer
47 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 ...
1
vote
1answer
109 views

Draw from HistogramDistribution with ParallelTable

I wanted to check something, but ran into troubles using HistogramDistribution in combination with ParallelTable. The code does the following: Compute a HistogramDistribution of some sample and use ...
1
vote
1answer
66 views

ParallelMap doesn't work with an Association. Is this a bug?

I receive a ParallelCombine::nopar1 error when executing ParallelMap[Identity, <|1 -> 1, 2 -> 2|>] Is this an ...
1
vote
1answer
42 views

Break out of ParallelDo

In a parallelised computation, I would like each kernel separately to break out of ParallelDo when it has finished going through the loop once. For a single kernel ...