How useful is a stride in arrays and matrices?

[StephenG1CMZ]

I have been looking at software implementing matrix and vector operations, such as BLAS (Basic Linear Algebra Subprograms). Many of these routines include a stride or increment parameter, such that for example SUM([1 2 3],1) returns 6 but (, 2) returns 4 as the sum of the 2 effective elements 1 3..

I can see how using a stride might be useful, for example allowing a vector to contain [x y x y] instead of having two vectors [x x] and [y y]. But also having two separate vectors could be useful too.

What I am not so sure of is how popular the use of a stride is in datasets, in particular on calculators, where the smaller Ram and less convenient data entry might encourage smaller non-strided matrices.

On the HP Prime AFAIK there is not an obvious Sigma(vector, stride) syntax, although I am sure that a syntax to implement that exists. But how useful would such functionality be on a calculator? Is there a need?