global variables - call function - parfor
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Hi all,
I am trying to parallelize my code which basically solve odes with different boundary condition. The problem is that my equations need global variable which seems to be reset when calling a parfor loop. I use matlab R2014a and here is an example of code that (I think) should work :
Main program :
global a
a=8;
b=zeros(10,1);
parfor i=1:10
b(i,1)=pluss(i);
end
b
function pluss :
function val=pluss(x)
global a
whos a
val=x+a;
It works fine with a for loop however with parfor the
who's a
gives as an answer
Name Size Bytes Class Attributes
a 0x0 0 double global
so the program stop running.
Does somebody has an idea how could I make this variable 'a' a 'real' global variable ?
thank you in advance,
Hugo P.
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Answers (3)
Edric Ellis
on 15 May 2014
Global variables are not synchronized between the desktop MATLAB and the workers, as described in the documentation. You should aim to refactor your code to remove the need for globals. (Perhaps you could post a simple reproduction showing why you currently need to use globals).
0 Comments
Hugo
on 15 May 2014
Edited: Hugo
on 15 May 2014
1 Comment
Edric Ellis
on 15 May 2014
You can avoid transferring the data multiple times by taking advantage of the Worker Object Wrapper.
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