Devon McCormick wrote: > I find the APL/J general use of "arrays" and what they are to be simple, > useful, and consistent. > I agree with Ralph that calling a 1xN matrix a row vector and an Nx1 > matrix > a column vector is, > at least, sloppy language.
I am not convinced. If you don't have row and column matrices (a) matrix multiplication is not associative (b) the results have the wrong shape mp=:+/ .* a=:1 2 b=:3 4 c=:5 6 vc=:2 1 $ c vb=:1 2 $ b va=:2 1 $ a a mp (b mp c) 117 (a mp b) mp c 121 a mp b 11 va mp vb 3 4 6 8 Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
