Unable to convert expression into double array

Dear all

In the code I would like to use sym function to calculate this function.But I keep getting this error.

"Unable to convert expression into double array.'

I=zeros(256,256);
syms t;
for i=1:256
    for j=1:256
        I(i,j)=1+cos(2*pi*(19.5+t)*i/1950/10^-4)-cos(2*pi*100*i);
    end
end

[duty duty]

Thanks！！

Answer 1

[Ameer Hamza]

You are initializing I as double matrix, initialize it as a symbolic matrix

syms t;
I = zeros(256,256, 'like', t);

for i=1:256
    for j=1:256
        I(i,j)=1+cos(2*pi*(19.5+t)*i/1950/10^-4)-cos(2*pi*100*i);
    end
end