Clear Filters
Clear Filters

get matrix in parfor

3 views (last 30 days)
vu ngothanh
vu ngothanh on 4 Apr 2016
Answered: Edric Ellis on 12 Apr 2016
Dear all,
I have this code
result=[]
for m=1:10
for k=1:100
for c=1:50
a=m+k*c;
b=m*k-c;
result=[result;a b];
end
end
end
I try to convert from for to parfor like this
result=[]
for m=1:10
parfor k=1:100
for c=1:50
a=m+k*c;
b=m*k-c;
result=[result;a b];
end
end
end
But there is a problem, "the variable 'result' used a value outside of the loop". I has searched from the site, but i'm not understand about the solution.
How can I fix it.

Answers (1)

Edric Ellis
Edric Ellis on 12 Apr 2016
You can't update the parfor reduction variable result inside the inner loop, you need to update it directly in the body of the parfor loop. You can work around this by making a new temporary reduction variable for each iteration of the parfor loop, and then update result once that's complete, like so:
result=[];
for m=1:10
parfor k=1:100
tmp = [];
for c=1:50
a=m+k*c;
b=m*k-c;
tmp=[tmp;a b];
end
result = [result; tmp];
end
end

Categories

Find more on Parallel for-Loops (parfor) in Help Center and File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!