Matlab - Symbolic mulitiplication matrice by operator

The Script multiply operator matrice U by matrice A . The script run on octave platform.
Download the file matrice1.m

% This script define symbolic  4*4 matrix A
% The script define matrix U as opertor
% The script solve the multilication U*A

% Load symbolic package, and initilize PYTHON variable.
pkg load symbolic
setenv PYTHON C:\ProgramData\Anaconda3\pythonw.exe

% Define Symbolic variables
syms x11 x12 x13 x14 x21 x22 x23 x24
syms x31 x32 x33 x34 x41 x42 x43 x44

% Matrice A
A = [ x11 x12 x13 x14
x21 x22 x23 x24
x31 x32 x33 x34
x41 x42 x43 x44 ]

% Operator Matrice U
U = [ 0 0 0 0
1 0 0 0
1 1 0 0
0 0 0 0 ]

disp('C = U*A')
 C = U*A

The result