Mathcad Express - speeding up vec My Mathcad Prime 11 trial period has recently ended, so I've been reviewing how some of my older Mathcad Express (E7 & E10, mostly) worksheets and functions perform under Mathcad Express 11.
While updating an array reshape function, I noticed that the performance was deteriorating as the array size increased. This in itself wasn't too surprising, but it was a lot slower than I'd have expected from an O(log(n)) algorithm. A mere 50,000 elements were taking 3 to 4 seconds to vectorize (confusing terminology in Mathcad terms, I know, but it is common in mathematics - see links at the bottom of this post)
reshape, however, used a vec variant to flatten the target array into a vector, before creating a suitably dimensioned array from the resulting vector, and vec proved to be the reason for the performance problem.
vec uses fold to apply a bespoke stacking function to its input argument. I wondered if there was a means of speeding it up and tried a
