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How to create data file and copying data on it for parallel programing in MATLAB?
You are quite right that trying to write to the same file from multiple workers will cause problems. Here's one way that you cou...

1 year ago | 1

Answered
How do you remove rows from tall arrays?
As the error message states, the only way to remove specific rows from a tall array is with a logical vector. In other words, th...

1 year ago | 1

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Answered
"parameter {0} must be a real scalar" error when using parfor
I think you need to use createConnectionForPool to make your database connection object and have it work correctly inside your p...

1 year ago | 3

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Answered
How to let a lab tell if another lab is idle or not in a spmd block at that time : isidle(labindex)
I can think of a few ways around this: As you suggest, labProbe can tell you if there's an incoming message ready to be receive...

1 year ago | 1

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When I use parfor in the program, the program seems to fall into an endless loop in the remoteparfor.m file, resulting in the program's delay in output.What's going on?
The file "remoteparfor.m" is part of the implementation of a parfor loop. The main job of this piece of code is to wait for resu...

1 year ago | 0

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reproducible and independent random stream generation in parfor loop
This topic is covered here in the documentation. You should not mix setting 'Seed' with setting 'Substream'. (The 'Seed' value s...

1 year ago | 2

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Answered
Running parfor loop in R2013a
Yes, Parallel Computing Toolbox was available for R2013a. Yes, in R2013a, you need to explicitly create the parallel pool using ...

1 year ago | 0

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Answered
parfor for movie writeVideo
The problem is that you're trying to send a VideoWriter object to the workers, and that's not allowed. A secondary problem is th...

1 year ago | 0

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Dramatic but intermittent slow down of parallel system calls
This sort of sporadic slowness can be extremely hard to track down. I'm not an expert on how MATLAB manages system calls, but I'...

1 year ago | 0

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Access composite variables after parallelpool shutdown
Unfortunately there is not. The contents of Composite (and distributed arrays) are always left on the workers until you explicit...

1 year ago | 0

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Answered
Multiple Parallel Jobs on Server
You say that "main.m" script uses 4 cores to do parallel computing. I presume this means that it contains a parfor loop. One way...

1 year ago | 0

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parfor treats variable as function
This is a limitation of parfor. The documentation here describes the principle reason, but doesn't quite show an example exactly...

1 year ago | 1

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How can I make more efficient use of parallel workers?
A couple of suggestions: you could consider using DataQueue rather than writing files to track progress on the workers. Yes, it ...

1 year ago | 0

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Answered
Passing composite variable to mex file
Unfortunately, there is no way to access the elements of a Composite from a MEX file. Is there any way you could run the MEX fil...

1 year ago | 0

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Answered
Move from parfor to parfeval?
To run using parfeval, you basically need to pull out the body of your parfor loop into a function, something like this: cellli...

1 year ago | 0

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Force CPU Parallel pool
There's no direct way to specify this using trainingOptions, but what you can do is disable the GPUs on the workers by running t...

1 year ago | 0

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How to use libpointer inside parfor loop?
I think you should be able to do this using parallel.pool.Constant. I think you might need 2 of them in fact - one to manage the...

1 year ago | 0

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Parfeval, Backgroundpool and Webread
Unfortunately, as you suspect, right now the only way to do this is to use a process pool via parpool('local') or similar.

1 year ago | 0

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How to specify GPU devices for parallel computing using "parfor"?
The documentation here describes how you might do this in general. Things get a little more complicated if you want to run more ...

2 years ago | 1

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pass Python object as argument to function in "parfeval"
One of the limitations of the MATLAB->Python support is that Python objects cannot be serialized. parfeval (and other parallel c...

2 years ago | 0

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decomposition in parfor failure
Unfortunately, I think you're hitting the sort of problem that was mentioned in this answer to the question you linked to - the ...

2 years ago | 1

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How can an infinitely running worker be gracefully terminated?
The simplest way to fix this is to use onCleanup to ensure that your fclose statement is executed. This is good practice anyway,...

2 years ago | 1

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Answered
How exactly does MATLAB calculate a sum of array elements by its sum() function? Does it use any compensated summation algorithm such as Kahan?
The outtype parameter to sum controls the numeric type used for summation, described in the doc. The default is that sum on sing...

2 years ago | 0

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How to slice these variables?
I think what you're trying to do is something like this, which doesn't work: N = 4; out = zeros(N, 3); try parfor idx = ...

2 years ago | 0

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How to store 2D arrays in a for loop inside a parfor loop?
I think you can do this simply by essentially "reshaping" the problem to satisfy the parfor requirement that the index expressio...

2 years ago | 0

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Passing a Global Variable to arrayfun for gpuArray
You can do this by using a nested function and variables in the containing parent workspace instead of global variables. Here's ...

2 years ago | 1

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Parallel pool constant with a parfor and for loop
Yes, parallel.pool.Constant is generally most useful when there are multiple parfor loops. (There are other use-cases such as wh...

2 years ago | 0

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How do I use SatelliteScenario Groundstation objects inside of a Parallel Computing Toolbox parfor loop
Thanks for reporting this problem. You can work around this for now like so: fetchOutputs(parfevalOnAll(@() delete(figure), 0))...

2 years ago | 0

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Answered
How to create interleaved complex from real gpuArray in mex?
Yes, complex mxGPUArray data is always stored in interleaved-complex format, see this doc page for details.

2 years ago | 0

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Answered
Fill structure in parallel loop
The main constraint here is the parfor "sliced output" requirement. Basically you cannot directly update a single struct using p...

2 years ago | 0