Function: matrix
Section: linear_algebra
C-Name: matrice
Prototype: GGDVDVDE
Help: matrix(m,n,{X},{Y},{expr=0}): mXn matrix of expression expr, the row
 variable X going from 1 to m and the column variable Y going from 1 to n. By
 default, fill with 0s.
Doc: creation of the
 $m\times n$ matrix whose coefficients are given by the expression
 \var{expr}. There are two formal parameters in \var{expr}, the first one
 ($X$) corresponding to the rows, the second ($Y$) to the columns, and $X$
 goes from 1 to $m$, $Y$ goes from 1 to $n$. If one of the last 3 parameters
 is omitted, fill the matrix with zeroes.
 %\syn{NO}