Questions on parallel computing in Mathematica.

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2
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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 ...
3
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2answers
84 views

Assignments in ParallelDo when using indexed variables

For convenience I use an indexed variables syntax to hold results of long computations for different integer parameters: ...
0
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0answers
23 views

Generating a list consisting of function values like in a triangular matrix

A goal is to generate a SymmetrizedArray of dimension n^k with specified symmetry (let it to be ...
0
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0answers
26 views

What is the right way to combine a Package, Module, ParallelTable and NIntegrate?

I am stuck with a curious problem. I would like to to have a package from which i can call a function test[path], which then performs a time consuming numerical ...
1
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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 ...
0
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2answers
86 views

Numerical 3D Integration in Mathematica [closed]

My question in short is: Is it possible to make numerical 3D integration in mathematica efficiently? Or am I gonna have to move this to C++? I feel this problem is way too trivial to go to C++, so ...
3
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0answers
42 views

Smart use of ParallelMap over Plus

I'm looking for ways to speed up calculation of a integral with a many-terms integrant. The obvious way is to go in parallel. I was surprised, but for some tests integration by ...
0
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0answers
34 views

Parallel calculation with SetOptions

Is it possible to distribute the effect of SetOptions to parallel kernels? Here is how I encountered the problem: I am trying to calculate a lot of numerical ...
1
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1answer
79 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 ...
0
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2answers
34 views

Parallel evaluation hangs before doing anything

[I use Mathematica 9.0.1.0 on OS X Yosemite 10.10.2.] I am experiencing difficulty with parallel evaluation that I am finding extremely perplexing to troubleshoot. I define the following function in ...
3
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2answers
155 views

NDSolve in Mathematica won't use all the cores avaiable

When I solve a system of differential equations in Matlab, the task manager shows that all the CPU cores are in use. This is not true when I solve the same system in Mathematica. I have six cores. ...
0
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0answers
36 views

Parallelize: No speed-up when using with FindMaximum

I have developed a program to compute the maximum value of an specific function multiple times, with different parameter values each time. I've been using the ...
4
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2answers
110 views

Using Throw within ParallelDo

I've noticed that I can't Throw from within a ParallelDo in the same way that I can from inside Do. For instance, the following will work as anticipated with Do but not with ParallelDo: ...
1
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0answers
47 views

ParallelMap not using all of the available kernels

Please note: I cannot provide the code here, since the project is far too big to post at any Internet forum. I have a computer with eight logical cores. I have Mathematica Version 10.0.2, and I am ...
1
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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
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0answers
14 views

SetSharedVariable on multi-dimensional array [duplicate]

I am trying to modify a multidimensional array inside a ParallelDo, but I get the error 'Symbol array is Protected'. How can I solve it? I attach here a minimal code to reproduce the error: ...
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 ...
1
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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: ...
2
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2answers
53 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
68 views

Launching 49+ local kernels fails in 10.0.2 [closed]

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
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0answers
31 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
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1answer
93 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
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. ...
1
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0answers
76 views

Avoid copying memory for each subkernel

Here is a simplified example illustrating my issue; ...
0
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0answers
63 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
41 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
57 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
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1answer
63 views

Why doesn't my expression evaluate at the subkernel?

Consider this code: ...
2
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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 ...
4
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1answer
136 views

Definitions are not distributed to parallel kernels

I have a small package with utilities, which looks like that: ...
0
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0answers
57 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
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1answer
75 views
1
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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 ...
2
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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
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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 ...
1
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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 ...
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0answers
115 views

Can GPU (CUDA) speed up LinearSolve?

Is there a way to use GPU (CUDA) to speed up LinearSolve?
2
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2answers
65 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
206 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
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0answers
51 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
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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
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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 ...
0
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0answers
33 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
108 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
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0answers
50 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
38 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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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 ...
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 ...
3
votes
0answers
160 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 ...