Error running concurrent process and storing results in array

[data pulverizer]

On Friday, 8 May 2020 at 13:36:22 UTC, data pulverizer wrote:
> ...I've disallowed calling BLAS because I'm looking at the 
> performance of the programming language implementations rather 
> than it's ability to call other libraries.

Also BLAS is of limited use for most of all the kernel functions, 
it's very useful for DotKernel but not as much for the others 
(there are many such functions) and no use for some others - 
which is another contributory factor to why I also chose kernel 
matrix calculations, you can't always call a library, sometimes 
you just need to write performant code.