topic Re: Bug in Prime with vectorization and prime operator? in Mathcad

Bug in Prime with vectorization and prime operator?

Werner_E — Sun, 08 Jun 2025 19:17:10 GMT

Found what looks to me like a bug.

The error message is not very helpful and rather an indication that it is actually an unintentional bug.

In Mathcad the convenient prime operator is not available and so we would have to use

Can't check if this way would work in Prime as I am limited to Express and that kind of 'programming' is a premium feature not available in Express.

In Prime we get the very same error when using a scalar argument and vectorize

Any comments on this?

Prime 4 worksheet attached

Re: Bug in Prime with vectorization and prime operator?

ttokoro — Sun, 08 Jun 2025 23:19:32 GMT

Prime 11 shows the same error. Symboric and then = can do it.

Re: Bug in Prime with vectorization and prime operator?

Werner_E — Mon, 09 Jun 2025 00:43:00 GMT

Yes, I tested with Prime 4, 6, 10 and 11 and all suffer from the same bug.

I suspect that it has something to do with the new way introduced with Prime to access vector elements by looking at the vector if it were a function. Not sure about that, but whatever the cause may be, I consider it a severe bug.

Interesting that it seems to be a numeric only problem.

It works with symbolic eval because the numeric evaluation only evaluates the expression directly to the left of it, which the symbolic engine already had calculated.

Re: Bug in Prime with vectorization and prime operator?

LucMeekes — Mon, 09 Jun 2025 14:25:41 GMT

Similarly:

The vectorised expression gives the error "This function requires at least 2 argument but is applied to 1."

Success!
Luc