MATLAB: How to integrate a signal sawtooth

numerical integration

I'm integrrating the signal sawtooth using the function "integral" such that "0" min limit and "i" is the max limit to get values of theta to plot it with time but there is an error 'Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.'
Can you help please ?
fs = 1000;
kf=1000;
t = 0:1/fs:2;
signal = @(tt) sawtooth(pi*2*tt+pi);
theta=[];
for i = (0:1/fs:2)
theta=2*pi*kf*integral(signal,0,i);
end
plot(t,theta[i])

Best Answer

Try this: 
fs = 1000;
kf=1000;
t = 0:1/fs:2;
signal = @(tt) sawtooth(pi*2*tt+pi);
theta=zeros(size(t));
for i = 1:numel(t)
    theta(i)=integral(signal,0,t(i));
end
figure
plot(t,theta)
It is necessary here to subscript ‘t’ and ‘theta’ in the loop to create the desired vectors.
Related Question