Procedure from library matrix.lib (see matrix_lib).
matrix.lib
addcol(A,r1,p,r2); A matrix, p poly, r1, r2 positive integers
matrix, A being modified by adding p times row r1 to row r2
Example:
LIB "matrix.lib"; ring r=32003,(x,y,z),lp; matrix A[3][3]=1,2,3,4,5,6,7,8,9; print(A); → 1,2,3, → 4,5,6, → 7,8,9 print(addrow(A,1,xy,3)); → 1, 2, 3, → 4, 5, 6, → xy+7,2xy+8,3xy+9