Question on a simple "parfor loop"

Hi There,

I have a simple parfor loop as belows

c=1;
a=0;
parfor i=-90:90
c=i+91;
a(c)=3;
end

I thought in this way, each iteration is independent and satisfy the rule of parallel computing, but i still get an error message " The variable a in a parfor cannot be classified". Any one could let me know the reason and how to fix the code?

Thanks.

Answer 1

[Walter Roberson]

parfor i=-90:90
  a(i+91)=3;
end

The parfor index variable must appear directly in the indexing expression, not as a variable computed based upon the indexing expression. This is a limitation on parfor to allow it to do static analysis.