An UndefinedFunction error was thrown on the workers with parfor

Hi,

I got the error

An UndefinedFunction error was thrown on the workers for 'x'.  This might be because the file containing 'x' is not accessible on the workers.  Use addAttachedFiles(pool, files) to specify the required files
to be attached.  See the documentation for 'parallel.Pool/addAttachedFiles' for more details.
Caused by: Undefined function or variable "x"

when running the simple code below. Can anyone please help me with this?

Thanks,

    clear all;
    clc;
    parfor n=1:1    
        for m=1:2    
            x{n}(m) = 1;
        end
        y = x{n}(1)
    end

[Walter Roberson]

Initialize x first and the problem will go away.

[Dave Lee]

Hi Walter,

Do you mean as below? I tried and it could run. However, Matlab highlights the error as below when I point to parfor or x (red underscores). Is that still good?

Thanks,

[Dave Lee]

Thanks! it helps.

Answer 1

[Walter Roberson]

x = cell(1, 1);

before the parfor.