Nice way to iterate through a triangular matrix

[rocco_sprmnt21]

Iterating over elements of upper triangular matrix, but cartesian indices are needed

Basically what I (think) I need is this function: https://stackoverflow.com/questions/27086195/linear-index-upper-triangular-matrix Of course I can just implement it, two lines of code. But that seems something that probably is needed quite frequently in matrix computations, so I am surprised I didn’t find it as a Base function. First I thought that most people would prefer constructing an iterator like (for a 3x3 matrix, for example): julia> for c in Iterators.filter(c -> c[1] < c[2], Carte…