Calculating Fourier Series Coefficients Using Custom Matlab Function

My attempt at creating such a function where it must have the three inputs x, w0, and N:

function[ak] = cal_fs(x, w0, N)
ak = zeros(1,2*N+1); %intialize a row vector of 2N+1 zeros
T = 2*pi/w0; %calculate the period and store in T
syms t;

for k = -N:N
ak = 1/T * int(x * exp(-1i*k*w0*t), t); % ak is fourier coefficient
end

Above is my attempt. I am trying to make a vector ak that contains all the fourier series coefficents as calculated by the equation above. I am new to Matlab and highly confused as to why i do not get an output of a matrix when I do the following:

syms x;
syms t;

x = 2*t;
w0 = 62;
N = 20;
cal_fs(x,w0,N)

[ha9981]

The problem is the output of cal_fs is not coming as a vector but rather a symbolic matrix 1x1. What am I doing wrong friends?

Answer 1

[Alexander]

You forgot the index for assigning to ak. Also do you want the indefinite integral or an integral from 0 to 2*pi/w0? I added the index and changed the integral:

function[ak] = cal_fs(x, w0, N)
ak = zeros(1,2*N+1); %intialize a row vector of 2N+1 zeros
T = 2*pi/w0; %calculate the period and store in T
syms t;
for k = -N:N
ak(1,1+k+N) = 1/T * int(x * exp(-1i*k*w0*t), t, 0, T); % ak is fourier coefficient
end

[Parul Saini]

Can we take piecewise continuous function with the same format of calculating fourier coefficients?

Answer 2

[Azzi Abdelmalek]

Try my submission http://www.mathworks.com/matlabcentral/fileexchange/37654-get-harmoniques-of-a-real-signal

[Kyon]

i have the RMS value and the angle values using the fourier block in simulink

what code to use to use rms and theta to plot fourier series ?