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I have two for loops running in my Matlab code. The inner loop is parallelized using Matlabpool in 12 processors (which is maximum Matlab allows in a single machine).
I dont have Distributed computing license. Please help me how to do it using Octave or Scilab. I just want to parallelize 'for' loop ONLY.
There are some broken links given while I searched for it in google.
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We can make a for-loop parallel using the multiprocessing pool. A process pool is a programming pattern for automatically managing a pool of worker processes. The multiprocessing. Pool class provides a process pool with helpful functions for executing for loops in parallel.
Can any for loop be made parallel? No, not any loop can be made parallel. Iterations of the loop must be independent from each other. That is, one cpu core should be able to run one iteration without any side effects to another cpu core running a different iteration.
In a parallel loop, the parallel processors execute the same code region, namely, the loop body, but with different data. Thus, parallel loops are a special kind of SPMD programming. Typically, parallel loops are used within a shared memory programming model, for example, OpenMP and Intel's Threading Building Blocks.
parfor is not really implemented in octave yet. The keyword is accepted, but is a mere synonym of for (http://octave.1599824.n4.nabble.com/Parfor-td4630575.html).
The pararrayfun and parcellfun functions of the parallel package are handy on multicore machines.
They are often a good replacement to a parfor loop.
For examples, see http://wiki.octave.org/Parallel_package. To install, issue (just once)
pkg install -forge parallel
And then, once on each session
pkg load parallel
before using the functions
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In Scilab you can use parallel_run:
function a=g(arg1)
a=arg1*arg1
endfunction
res=parallel_run(1:10, g);
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