Questions on parallel computing in Mathematica.

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2
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0answers
18 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 ...
1
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0answers
39 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
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1answer
67 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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0answers
38 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. ...
4
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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
247 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
43 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 (...
2
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0answers
79 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
96 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 ...
3
votes
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 ...
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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:- ...
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
141 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 ...
1
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0answers
73 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: ...
20
votes
1answer
607 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 ...
3
votes
1answer
125 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 ...
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: ...
2
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1answer
82 views

ParallelEvaluate: Evaluation Rules and Increment

I'm trying to understand how ParallelEvaluate works, considering the two following snippets: ...
4
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0answers
124 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 ...
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: ...
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". ...
1
vote
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
46 views

A problem with parallelize

I am experimenting with Parallelize and ParallelTable This is the code I am using: ...
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?
0
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1answer
81 views

ParallelTable not firing

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1
vote
1answer
55 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
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: ...
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
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0answers
74 views

ParallelTable and expensive functions

I would like to build up a 2D-Table using ParallelTable as follows ...
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

ParallelTable Works in Regular Notebook but Gives Error When Packaged

Consider the following: ...
0
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1answer
206 views

Parallel computation of NDSolve and a problem

I used this code to solve a system of differential equations: ...
0
votes
1answer
162 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 ...
0
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0answers
34 views

KernelObject::rdead on local kernels

I'm trying to parallelize some tasks which involve fetching data from a URL and processing it. This is the code: ...
3
votes
1answer
57 views

Creating a parallelizable DiscretePlot

To my knowledge, DiscretePlot cannot be parallelized, although one can simulate the default behavior of DiscretePlot and get the ...
1
vote
2answers
128 views

Do multiple instances of Mathematica run completely independently?

Let me simplify the problem I am trying to solve so that the issue I face is highlighted. Say, I want to generate $n$ samples of a Gaussian random variable. I have a script (say ...
14
votes
1answer
310 views

Making Monte Carlo simulation with ParallelTable

I would like to to MonteCarlo simulations of various regressions - basically, doing OLS under various conditions to test approaches. On my macpro 2x 2.8 GHz quad core Xeon, 32 Gb RAM DDR2 @ 667 Mhz, ...
0
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0answers
653 views

Fastest way to create a NxNxNxN dimensional matrix

I have a function that outputs a complex number Func[x_,y_]:= blah blah; I have constructed a table of all possible values of this function. ...
3
votes
0answers
66 views

LibraryLink parallel performance

I'm trying to use a LibraryLink function in parallel. It is an embarrassingly parallel problem, so that no dependency between those parallel tasks. However I can only get the parallel efficiency about ...
0
votes
2answers
74 views

Distributing value of variable to specific kernel

I want to distribute the value of a variable to a specific kernel in a parallel computing setup. Using DistributeDefinitions of course does the job, but it ...
11
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5answers
1k views

What is the fastest way to extract a substring from a huge string?

I develop an algorithm to find the most common substrings of a given length n up to a certain distance l in front of a pattern p in a huge sequence S. E.g. I want to find the most common hexamers ...