IS_PARALLEL_WORKER being executed by Parallel Computing Toolbox?
detects if being executed by Parallel Computing Toolbox e.g. in a parfor loop
Reference: https://www.mathworks.com/help/parallel-computing/getcurrenttask.html
test by: >> is_parallel_worker
ans = logical 0
>> parfor i = 1:1, is_parallel_worker, end Starting parallel pool (parpool) using the 'local' profile ...
ans = logical 1