Questions on parallel computing in Mathematica.

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13 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
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1answer
64 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 ...
1
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1answer
122 views

Parallel numerically integrated function can't be plotted [on hold]

I've been working on a problem where I need to integrate a function numerically. The function is quite complex and it takes almost an hour for Mathematica to make a plot. To speed the process up I ...
1
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0answers
38 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?
1
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0answers
80 views

Why does ParallelTable give different answer than Table [closed]

Consider the following code a0 = 6.; ls1 = ParallelTable[k, {k, -π/a0, π/a0, π/a0/100}]; ls2 = Table[k, {k, -π/a0, π/a0, π/a0/100}]; ls1 == ls2 (*False*) Why ...
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0answers
37 views

NMaximize stops evaluating my function when run in parallel

I am trying to maximize the results of a Monte Carlo simulation with respect to some input variables. ...
3
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1answer
124 views

Parallel kernel and front end

I have a piece of code which looks like this: ParallelTable[ Monitor[ Table[ <code here> ,{i,i1,i2]; ,i]; ] so basically a ...
4
votes
1answer
59 views

Parallelizing sparse array construction

I have a very large sparse array, and the computation of individual matrix elements is fairly expensive. The Matrix is Hermitian and traceless, so I would like to construct only the sub-diagonal ...
6
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1answer
243 views

Optimizing Monte Carlo simulation of a Pred-Prey model

My assignment and code As part of an assignment for one of my classes, I'm trying to run a "massive" Monte Carlo simulation in Parallel on the follow model: ...
1
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1answer
41 views

Connect to Windows kernel from Linux computer

I've seen many questions regarding the connection to a Linux machine from a Windows one, but I need to do the opposite. Situation: I have Mathematica on my Linux laptop (...
3
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1answer
155 views

Issue in ParallelTable after evaluating another function using NDSolve and FindRoot. What is wrong with this inverse?

I am trying to find the inverse of a function which is defined through NDSolve and NIntegrate. The question is pretty similar ...
2
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0answers
78 views

OpenCL vs. CUDA with Mathematica

I am thinking about using GPU programming with Mathematica using a MacBook Pro with a NVIDIA GPU. At this page, the Mathematica documentation says "Programming OpenCL in the Wolfram Language is simple ...
6
votes
2answers
95 views

Communication between local kernels

this is my first post but you have already helped me so many times that I have to start by saying thanks a lot! I have a really long calculation to do, and I have used the Evaluation->Kernel ...
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0answers
39 views

Placing package in existing Utilities` context has odd paraellelization effect

I noticed this in V.10 but possibly it was in effect in V.9. I have a package which in simplified form looks like:- ...
20
votes
1answer
603 views

Mma 10: Half the parallel power (Macs)?

Here is a comparison of the parallel kernels launched under Mathematica under v9 and v10, on the same identical current 2014 R2-D2 Mac Pro ... [ Update: Valerio has commented that the same issue ...
0
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1answer
76 views

ParallelMap returns incorrect results over Map

I've written a function to pull in the useful column of a large data file: ...
6
votes
0answers
117 views

Partial Differential Equation in Parallel

is there any native way to implement multi-core parallel solving of PDE in Wolfram Mathematica? WM 10 now supports Finite Elements Method, but it is actually useless without parallelization. Usually ...
2
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0answers
137 views

ParallelSum in Mathematica 9 vs 10

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

strange timing behavior

The following code is from a book about Mathematica. ...
0
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0answers
43 views

Shared variable impacting speed? [duplicate]

I am using a shared variable as a progress indicator ( via SetSharedVariable[counter] and then Dynamic[counter]), to keep track ...
2
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0answers
42 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: ...
1
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0answers
72 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: ...
0
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0answers
46 views

Need to parallelize function f in a iteration

I don't have experience using Mathematica for parallel calculation. I need to do something simple to parallelize the calculation of f which is calculate each time n iterates: ...
25
votes
1answer
530 views

Is it safe to launch/close kernels in the middle of a parallel calculation?

It appears that it is possible to launch additional kernels (or close existing ones) during a parallel calculation. The newly launched kernels will be utilized for the rest of the calculation. ...
6
votes
2answers
226 views

Does Eigenvalues evaluate in a parallelized way?

I use mathematica on a computer with linux operating system. The computer has 2 cpus and each cpu has 4 cores, so there are totally 8 cores available. Now I got confused with whether the evaluation ...
2
votes
1answer
82 views

ParallelEvaluate: Evaluation Rules and Increment

I'm trying to understand how ParallelEvaluate works, considering the two following snippets: ...
19
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1answer
2k views

Why won't Parallelize speed up my code?

What reasons are there that can cause parallelized Mathematica code not to run with full performance?
4
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0answers
122 views

How to force the compilation language to be C++ (not C) in CreateExecutable or CreateLibrary

I'm trying to speed up a section of a Mathematica 9.0.1 notebook by performing some calculations in C++ with the Cilk Plus and Threading Building Blocks tools available for the Intel C++ 14.0 compiler ...
3
votes
1answer
163 views

Optimization of power tower fractal generator [closed]

I tried to optimize the code for generating power tower fractals from here. As the author suggested, I tried to memorize the points already tested in a list. Here is my code : ...
0
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0answers
15 views

How can I set global computation options ($MaxPiecewiseCases) for parallel kernels? [duplicate]

I'm trying to do a calculation in parallel that requires setting $MaxPiecewiseCases. How can I do this? This small test case doesn't work for me: ...
8
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1answer
124 views

Experimental`NumericalFunction in NMinimize solution

I try to make a number of optimizations using this code: ...
2
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1answer
225 views

Parallel evaluation and memory use

I have never used Mathematica's parallel evaluation before and have some trouble getting it to work properly. For the record, I am running Mathematica 9 on Linux with an Intel Core i7 processor (4 ...
0
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0answers
28 views

Notebook stops using extra kernels after some time

Have a mathematica .nb job where I've programmed to run on parallel. Everything goes fine for about an hour but after this most kernels just stop being used by the program. I can see this happing in ...
1
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1answer
27 views

$IterationLimit and parallel computing

Short question: How can you set $IterationLimit for parallel computation? I thought just setting $IterationLimit = Infinity ...
0
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0answers
85 views

Cluster integration: Problem connecting to Sun Grid Engine

I'm trying to launch some kernels in a cluster engine running Sun Grid Engine using Cluster integration. But I'm getting the error "Cannot find components required for SGE". ...
2
votes
2answers
113 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 ...
1
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0answers
82 views

Diagonalization in parallel

I would like to diagonalize one unitary non-sparse matrix of size 12870 with complex number entries (not symbols, this is really a numerical problem). Is is possible to make eigensystem run in ...
0
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1answer
81 views
0
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1answer
46 views

A problem with parallelize

I am experimenting with Parallelize and ParallelTable This is the code I am using: ...
1
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1answer
54 views

Using parallel computing to build a matrix recursively

I am trying to compute the product of a sequence of matrices using the command ParallelDo. Of course, if I use the simpler command ...
0
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0answers
42 views

How to parallelize a the calculation of a vector function which is inside a recursive formula

I need some help with parallelizing the calculation of a vector function F which is inside a recursive formula. An example of the code is below for few iterations. ...
2
votes
0answers
74 views

ParallelTable and expensive functions

I would like to build up a 2D-Table using ParallelTable as follows ...
0
votes
1answer
205 views

Parallel computation of NDSolve and a problem

I used this code to solve a system of differential equations: ...
0
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1answer
56 views

ParallelTable and plotting result of own define funtion

I define function which return a list of numbers ...
3
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1answer
56 views
0
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1answer
161 views

Parallel computation of a system of differential equation

I need to solve a system of differential equations which contains, at minimum, ten thousands of differential equations. Actually, I am trying to solve density matrix equation. It's like something ...
6
votes
1answer
105 views

Garbage collection for memoized functions on subkernels

I have a top-level function which operates on some data: findBestIntegers[data_]:=ParallelMap[optimize,data] which makes parallelized calls to an optimization ...
2
votes
1answer
118 views

Copy a variable to a specific kernel in Mathematica [closed]

I would like to copy some parameter from the main Kernel of Mathematica to the parallel kernels available. So I'm running now a command like: ...
0
votes
1answer
83 views

Can ParallelDo speed up a counting problem?

How to make parallelize the following code keeping the same "idea". The example I have in mind is more complicated, but I would like to know if a program of this structure can be parallelized? ...
0
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0answers
63 views

How to parallelize this code

Here I obtained one code which should tests some zeros of the poly for various g, but sometimes I have to many cycles because of step and I need to parallelize the running on all cores. Classical ...