>>>error: 'sawtooth' undefined near line 17 column 6
error: 'square' undefined near line 17 column 6
>>>error: 'x1' undefined near line 17 column 21
error: evaluating argument list element number 2
>>>error: 'x2' undefined near line 18 column 21
error: evaluating argument list element number 2

% program to plot a saw tooth and square wave
fs = 10000;
t = 0:1/fs:1.5;
x1 = sawtooth(2*pi*50*t);
x2 = square(2*pi*50*t);
subplot(211);plot(t,x1);axis([0 0.2 -1.2 1.2]);
xlabel('Time (sec)');ylabel('Amplitude');title('Sawtooth Periodic Wave');
subplot(212);plot(t,x2);axis([0 0.2 -1.2 1.2]);
xlabel('Time (sec)');ylabel('Amplitude');title('Square Periodic Wave');
set(gcf,'Color',[1 1 1]);

sudo apt-get -q -y install octave-signal