Questions on parallel computing in Mathematica.

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2answers
168 views

How to confirm that computation uses multiple CPUs?

UPDATE: I should have made clear that I'm looking preferably for solutions that work on a text-only interface. I've fixed this omission below. I'm looking for some Mathematica expression whose ...
0
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0answers
34 views

Running complex functions in parallel

I've got a module containing a loop and multiple calls to other functions, i.e. ...
0
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0answers
35 views

How to parallelize a sequential program? [on hold]

I asked this question and I got good answers, but now when I try to make the computing in parallel with this command ...
3
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1answer
186 views

Alternatives to For/Do Loop to optimize indexing Matrix

I am trying to optimize my code that searches for elements in the rows of matrix that are greater than 0. Then use that position to grab the element from other matrix. I use the do loop to iterate ...
1
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1answer
39 views

How to see Monitor temporary cell with ParallelSubmit?

I have a function to load large files into a "HSQL(Standalone)" database for processing that uses Monitor to update the ...
1
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1answer
49 views

Suppress “From KernelObject” when printing in ParallelDo

Is there a way to avoid printing "From KernelObject[n, local]" when Print[] or WriteString[] is used in a parallel computation? ...
2
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1answer
21 views

How to avoid this Parallel Error

I want parallelize one task, but got some stupid error. I don't know why i got it and how to fix it. I have 2 examples. One works: ...
2
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0answers
40 views

Parallelize Dateset query

I would like to evaluate a Dataset query in parallel, my latest approach being: ...
1
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0answers
43 views

Paralell computing - divisors of large numbers [closed]

Program should return a list of all the divisors of n!-1 for n=50,51,...,59 using parallel computing. Here is my current ...
1
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0answers
72 views

Speed differences between Table, Replace, Array, Map, and AssociationMap

EDIT: Actually, it looks like part of this is bogus—Array doesn't actually work on this input (I'm often a little shaky on what kind of input, exactly, works for ...
1
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0answers
22 views

Launching specific remote kernels in parallel

For some reason I found that my numerical integration runs much faster on Mathematica 9 than on Mathematica 10. Since I sent my calculation to a cluster with 24 cores with the following command <...
1
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1answer
54 views

ParallelTable local variables don't update precision

I'm finding that precision of variables updated outside ParallelTable don't update inside of it the way I'd hope. Here's the minimal code that demonstrates my point: ...
9
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0answers
101 views

Smart use of ParallelMap over Plus [on hold]

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
33 views
0
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0answers
23 views
4
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0answers
61 views

Problem with Parallelization when using Packages

I tried to find a solution to my problem in several answers posted in MSE but due to lack of my knowledge on parallelization territory, I couldn't figure out solution to my problem. I have a big code ...
12
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1answer
165 views

DistributeDefinitions and synchronization in Mathematica 10

The command DistributeDefinitions[z] installs all current definitions for z on the local kernels. A simple example: we assign ...
0
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0answers
50 views

Can parallelization speed up FindClusters?

I have a clustering task that would take FindClusters 2-3 months1 to complete. Can this calculation be sped up with parallelization? (FWIW, the data to be ...
9
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3answers
1k views

Parallelization works, but does not use all CPU power

I've written code which involves Parallelize@Cases. When I evaluate, I find that all 16 cores are being used, but not fully; in other words all cores are active, but the total CPU usage is only 50%. ...
2
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0answers
27 views

ParallelDo issue with SQLExecute (SQLite) [closed]

This code run as expected if I use Do[...], but if I use instead ParallelDo[...], as in the code bellow, the SQL INSERT statements seems to be completely ignored. In both cases, the filename is ...
13
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3answers
428 views

Package found with `Needs`, but not with `ParallelNeeds`

I want to use a self-written package in a parallel computation. However while Needs["mypackage`"] works without problems, ...
7
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1answer
42 views

How to ensure that a package is always loaded on startup, even in parallel kernels?

Is there a robust way to ensure that a package is always loaded on startup, even in parallel kernels? Parallel kernels do not read Kernel/init.m.
4
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1answer
51 views

Cell evaluation and parallel kernels

Is it possible to simply force Mathematica to evaluate one cell with let's say kernel A and another cell with kernel B etc. so that they can be evaluated in parallel? There is a similar answer here ...
5
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1answer
496 views

Is there a method to send different Cell evaluation to different core?

I am running Mathematica on a computer with multi CPU and every CPU has multicore. I am wondering if there exist a method to send different cell evaluation to different core? So if I already have a ...
3
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0answers
30 views

Where do DistributeDefinitions and ParallelNeeds put their definitions for newly-launched kernels to find

I'm sorry to keep banging on the definition distribution bell, but here is another (hopefully well-focused enough) question on that vein. If one is trying to distribute the definitions in a package ...
0
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0answers
18 views

ParallelDo does not work, when using variables from other parts of the script

I have a script doing a large amount of calculations with very big matrices that takes so long; so, I want to parallelize pieces of the script to be executed on multiple kernels. For instance, the ...
7
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1answer
64 views

Run several input cells in parallel

I have a notebook with several input cells that produce data which is then plotted into separate graphs. Since I do not want to save the results, because it makes the file huge, I keep the ...
0
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0answers
24 views

Make an existing solution for monitoring parallel jobs robust against dying kernels

Is there any chance to make the solution by @David here http://mathematica.stackexchange.com/a/1562/21606 more robust in the following sense: In my case, some parallel kernels die regularly during ...
5
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1answer
48 views

How to understand the different output of two UnsetShared?

Update From technical support, Thank you for contacting Wolfram Technical Support. I understand that you are reporting an issue with UnsetShared deleting the shared variable after a second ...
6
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1answer
137 views

Calculate the ESP Grid based on Density Grid

I want to build a fast way to convert a density grid file into a grid file of the respective electrostatic potential (ESP; also known as MEP, the molecular electrostatic potential). This ...
2
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0answers
55 views

KernelObject appears dead problem [closed]

my cluster got 24 cores And I use this setting to do parallel computing ...
4
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1answer
108 views

Can a package append its context to $DistributedContexts?

I am writing a package (for reference, this one) which I use extensively in parallel computations, and to lighten the coding load on the 'run-time' notebook, I want my package to sit on the ...
3
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0answers
35 views

How to make use of multithread feature of Eigenvalues in ParallelDo or ParallelTable [duplicate]

In mathematica, Eigenvalues is implemented internally using intel MKL. When running Eigenvalues[RandomReal[1.,{2000,2000}] ...
2
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1answer
68 views

Can this simple loop with several counters be improved or parallelized

I am running the following calculations. The timing for H = 2000 is about 8 days on my machine. Can this be parallelized or improved upon in some other way. Also I am trying to avoid storing the ...
4
votes
1answer
58 views

How to Export from ParallelDo? [duplicate]

I'm running a simulation with parallel, and I want the results from each parameter set exported to a file whenever it's done (because the parameter space is huge and my computer doesn't have enough ...
6
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1answer
109 views

Local logfiles for remote kernels

I'd like remote slave kernels to produce log files on my local machine, subject to the following constraints: 1) I don't want to install a distributed filesystem or do other administrative work on ...
3
votes
1answer
55 views

Execute a function in parallel on different cores?

Suppose I have a function f which takes a list and does something with it: ...
10
votes
2answers
203 views

ParallelTable behaves differently when it is run inside a package

I've been butting my head against some very weird behaviour by ParallelTable, and its interaction with packages, over the past few weeks, and making relatively ...
1
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0answers
42 views

mathematica example for parallel run

I want to run a parallel mathematica example via a PBS script. I am not expert in this application, instead as a system administrator, I have to be sure that users are able to submit parallel jobs to ...
4
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1answer
45 views

$DistributedContexts and ParallelEvaluate

This is a small question regarding the relationship between the $DistributedContexts variable and the ParallelEvaluate command. ...
35
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5answers
3k views

Is it possible to speed up ContourPlot on multi-core machines?

It is not very difficult to face a function for which ContourPlot works too slow. And it seems natural that this function can be parallelized well. Anyway, naive <...
4
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0answers
43 views

Is there a clean way to parallelize multi-index tables?

The documentation of ParallelTable indicates that if you want to parallelize the evaluation of a table of more than one dimension, such as ...
4
votes
2answers
228 views

Mysterious behaviour of ParallelTable

This question is related to Export bug in combination with ParallelTable?. The following code shows an even stranger bug than in the upper question. The y-axis should always be logarithmic, but in ...
3
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1answer
34 views

Skipping commented in a stream from OpenRead

Is there a solution to skip comments in text files that are imported with OpenRead? I know there are solutions for Importand <...
4
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1answer
51 views

How can I access memoized values from parallel evaluation? [duplicate]

I want to evaluate a table of functions with ParallelTable. Here is the serial code: ...
3
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1answer
81 views

How to simultaneously monitoring parallel computations in different Kernels?

I have a question about monitoring parallel processes. Let's suppose that I am running the following code with 5 active Kernels. ...
8
votes
1answer
203 views

Export bug in combination with ParallelTable?

I am programming with Mathematica 10.3.1.0 on Windows 10 Professional 64 Bit and have an i7-4940-MX 3,1 GHz processor (4 cores). When I use in the example code below ...
4
votes
2answers
229 views

Elegant way to partition list to be faster than `ParallelTable` (using `ParallelSubmit`), or some alternative?

Suppose you have a function fun[x_] := (Pause[.05*x]; x^2); of which you know that its evaluation time increases with its argument - in this case obviously ...
1
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1answer
41 views

Customized `ParallelTable` - Automate `ParallelSubmit` - Possibly an issue with `HoldAllComplete` attribute

Related to this question and in particular its answer I am trying to wrap everything into a new parallelTab function that takes into account some cost per job, ...
0
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1answer
51 views

Improving performance Importing Table

I am currently working on mathematica script on a Raspberry Pi, which will periodically (10 secs) be launched by a bash script. However the runtime of my script really isn't the best. It's actually ...