Creating a Parfor loop for multiple function evaluation

Hello. I want to use parfor to reduce the calculation time for a loop I have by evaluating 6 functions at the same time. Could you please help me out with this:

The general form of the loop in my m file is:

x=rand(100,20);
global fidr_m;
fidr_m= fopen('C:/results.txt','w');   %%???
for i=1:100
     Y(i)=func(x(i,:))
end

and my function (func) includes some lines to generate a unique text file from a base file depending on the looping variable (i=1:100) and run a very costly function WW.

function y = func(X)
if isempty(count)
    count = 1;
else
    count = count +1;
end

BasePath='C:/MyComputer/';
BaseName='Comp';
File = strcat(Basename, BaseName, num2str(count),'.txt');
y=WW(File,X);

XX=[X,y];
global fidr_m;
if fidr_m==-1
   error('can not open the file');
end
fprintf(fidr_m, '%f\t', XX);
fprintf(fidr_m,'\n');

Answer 1

[Walter Roberson]

You do not define count in the function before you use it.

global variables are not copied between workers.

You cannot use a worker to do i/o on a file that you open in a different worker.