Error using plot Data must be numeric, datetime, duration or an array convertible to double.

This is my code

N=[randi([1,5],1,2),randi([10,50],1,2),randi([100,500],1,2)];
t=[-10:0.01:10];
tau=2*pi/3
for i=1:length(N)
    phi = exponential(N(i),t,tau);
    subplot(3,1,i)
    plot(t, phi,'b-')
end
% and here's my code for the functions
function phi = exponential(N,t,tau)
syms t
w=1;
for i = 1:length(tau)
    T = tau(i)
    f = (1)
    do = (1/(2*pi)) * int(f,t,-T/2,T/2);
    doz = double(do)
    d0vec(i)=doz
end
for i=1:length(N)
    for n=1:N(i)
        fun = 1*exp(N*t*w*j);
        dn = (1/(2*pi))*int(f*cos(n*pi*t),t,-T/2,T/2);
        ddn = double(dn);
        dnz(n) = ddn;
    end   
    dnhar{i} = dnz;     
end
for i=1:length(N)
    ef = 0;
    for n=1:N(i)
        estf=((dnhar{i}(n))*exp(j*w*N*t));
        ef = ef+estf
    end
    ftarray = ef+doz
end
phi = eval(ftarray);
end

I am supposed to calculate and graph the nth term of fourier exponential series.

Answer 1

[KSSV]

Variable phi used in the plot is a symbolic variable.

1/3 - (310775629405771*exp(t*4i))/576460752303423488

You cannot plot that striaght away using plot. Read about subs, get tvalues substitute values in there convert them into number using double and then plot.

Read about subs, double.

Also have a look on ezplot, fplot.

[Jiyoon Kim]

you're my life saver. Thank you so much!!