% -*- texinfo -*-
% @deftypefn {Function File} {} convmtx (@var{a}, @var{n})
% If @var{a} is a column vector and @var{x} is a column vector
% of length @var{n}, then
%
% @code{convmtx(@var{a}, @var{n}) * @var{x}}
%
% gives the convolution of of @var{a} and @var{x} and is the
% same as @code{conv(@var{a}, @var{x})}. The difference is if
% many vectors are to be convolved with the same vector, then
% this technique is possibly faster.
%
% Similarly, if @var{a} is a row vector and @var{x} is a row
% vector of length @var{n}, then
%
% @code{@var{x} * convmtx(@var{a}, @var{n})}
%
% is the same as @code{conv(@var{x}, @var{a})}.
% @end deftypefn
% @seealso{conv}