ncrat.lib
LIB "ncrat.lib"; ncInit(list("x", "y")); ncrat f = ncratFromString("x+y"); matrix A[2][2] = 1, 2, 3, 4; matrix B[2][2] = 5, 6, 7, 8; matrix M = ncratEvaluateAt(f, list(x, y), list(A, B)); print(M); ==> 6, 8, ==> 10,12