adding a row to a matrix with variable

[Jsather]

Off topic but related: Why is the row/col number in ADDROW and ADDCOL not optional? I'm sure 100% of us assume if you left it out, the prime would just append the specified row or column on the end. As it is, absence of row/col number generates a syntax error.

This would be a low maintenance change, completely backwards compatible, and certainly an improvement. Just hoping the right people notice and deem it worthy of addition to the revision suggestion list.