Everything being the same, then why does matrix C give different values in the two codes?

All the values are the same in both the codes, then why does matrix C give different values in both the codes?

code1:

u=[30 50 110];
M=10; 
N=4;  
K=3;  
d=0.5;

fn=@(u,k) exp(1j*2*pi*d*(0:k-1).' * sind(u));

A=fn(u,M);
B=fn(u,N);
C=kron(B,A);

code2

u=[30 50 110];
M=10; 
N=4;  
K=3;  
d=0.5;
C = STM(u,M,N,d);
function C = STM(u,M,N,d)
    
    A=exp(1j*2*pi*d*(0:M-1).'*sind(u));
    B=exp(1j*2*pi*d*(0:N-1).'*sind(u));

    C = zeros(size(A, 1)*size(B, 1), length(u));
    for idxK = 1 : 1 : length(u)
        C(:, idxK) = kron(B(:, idxK), A(:, idxK));
    end
end

Answer 1

[Cris LaPierre]

Because they are not the same?

Your output should be [size(A, 1)*size(B, 1), size(A, 2)*size(B, 2)]

See the More About > Kroeneker Tensor Product for what kron is calculating.

[Sadiq Akbar]

Thanks for your response. But the size of matrix C is 40 x 3 not 40 x 9 here

[Cris LaPierre]

Then you misunderstand what the Kroeneker Tensor Product is.

C is a 40x9 matrix in your first code.

u=[30 50 110];
M=10; 
N=4;  
K=3;  
d=0.5;

fn=@(u,k) exp(1j*2*pi*d*(0:k-1).' * sind(u));

A=fn(u,M);
B=fn(u,N);
C=kron(B,A)

C = 
   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i   1.0000 + 0.0000i
   0.0000 + 1.0000i  -0.7418 + 0.6706i  -0.9821 + 0.1883i   0.0000 + 1.0000i  -0.7418 + 0.6706i  -0.9821 + 0.1883i   0.0000 + 1.0000i  -0.7418 + 0.6706i  -0.9821 + 0.1883i
  -1.0000 + 0.0000i   0.1006 - 0.9949i   0.9291 - 0.3699i  -1.0000 + 0.0000i   0.1006 - 0.9949i   0.9291 - 0.3699i  -1.0000 + 0.0000i   0.1006 - 0.9949i   0.9291 - 0.3699i
  -0.0000 - 1.0000i   0.5925 + 0.8056i  -0.8428 + 0.5383i  -0.0000 - 1.0000i   0.5925 + 0.8056i  -0.8428 + 0.5383i  -0.0000 - 1.0000i   0.5925 + 0.8056i  -0.8428 + 0.5383i
   1.0000 - 0.0000i  -0.9797 - 0.2003i   0.7263 - 0.6874i   1.0000 - 0.0000i  -0.9797 - 0.2003i   0.7263 - 0.6874i   1.0000 - 0.0000i  -0.9797 - 0.2003i   0.7263 - 0.6874i
   0.0000 + 1.0000i   0.8611 - 0.5084i  -0.5839 + 0.8118i   0.0000 + 1.0000i   0.8611 - 0.5084i  -0.5839 + 0.8118i   0.0000 + 1.0000i   0.8611 - 0.5084i  -0.5839 + 0.8118i
  -1.0000 + 0.0000i  -0.2978 + 0.9546i   0.4205 - 0.9073i  -1.0000 + 0.0000i  -0.2978 + 0.9546i   0.4205 - 0.9073i  -1.0000 + 0.0000i  -0.2978 + 0.9546i   0.4205 - 0.9073i
  -0.0000 - 1.0000i  -0.4192 - 0.9079i  -0.2421 + 0.9702i  -0.0000 - 1.0000i  -0.4192 - 0.9079i  -0.2421 + 0.9702i  -0.0000 - 1.0000i  -0.4192 - 0.9079i  -0.2421 + 0.9702i
   1.0000 - 0.0000i   0.9198 + 0.3924i   0.0551 - 0.9985i   1.0000 - 0.0000i   0.9198 + 0.3924i   0.0551 - 0.9985i   1.0000 - 0.0000i   0.9198 + 0.3924i   0.0551 - 0.9985i
   0.0000 + 1.0000i  -0.9455 + 0.3257i   0.1340 + 0.9910i   0.0000 + 1.0000i  -0.9455 + 0.3257i   0.1340 + 0.9910i   0.0000 + 1.0000i  -0.9455 + 0.3257i   0.1340 + 0.9910i
   0.0000 + 1.0000i   0.0000 + 1.0000i   0.0000 + 1.0000i  -0.7418 + 0.6706i  -0.7418 + 0.6706i  -0.7418 + 0.6706i  -0.9821 + 0.1883i  -0.9821 + 0.1883i  -0.9821 + 0.1883i
  -1.0000 + 0.0000i  -0.6706 - 0.7418i  -0.1883 - 0.9821i  -0.6706 - 0.7418i   0.1006 - 0.9949i   0.6023 - 0.7983i  -0.1883 - 0.9821i   0.6023 - 0.7983i   0.9291 - 0.3699i
  -0.0000 - 1.0000i   0.9949 + 0.1006i   0.3699 + 0.9291i   0.7418 - 0.6706i   0.5925 + 0.8056i  -0.4412 + 0.8974i   0.9821 - 0.1883i   0.0885 + 0.9961i  -0.8428 + 0.5383i
   1.0000 - 0.0000i  -0.8056 + 0.5925i  -0.5383 - 0.8428i   0.6706 + 0.7418i  -0.9797 - 0.2003i   0.2642 - 0.9645i   0.1883 + 0.9821i  -0.7336 - 0.6796i   0.7263 - 0.6874i
   0.0000 + 1.0000i   0.2003 - 0.9797i   0.6874 + 0.7263i  -0.7418 + 0.6706i   0.8611 - 0.5084i  -0.0779 + 0.9970i  -0.9821 + 0.1883i   0.9999 + 0.0122i  -0.5839 + 0.8118i
  -1.0000 + 0.0000i   0.5084 + 0.8611i  -0.8118 - 0.5839i  -0.6706 - 0.7418i  -0.2978 + 0.9546i  -0.1113 - 0.9938i  -0.1883 - 0.9821i  -0.7499 + 0.6615i   0.4205 - 0.9073i
  -0.0000 - 1.0000i  -0.9546 - 0.2978i   0.9073 + 0.4205i   0.7418 - 0.6706i  -0.4192 - 0.9079i   0.2964 + 0.9551i   0.9821 - 0.1883i   0.1127 - 0.9936i  -0.2421 + 0.9702i
   1.0000 - 0.0000i   0.9079 - 0.4192i  -0.9702 - 0.2421i   0.6706 + 0.7418i   0.9198 + 0.3924i  -0.4710 - 0.8821i   0.1883 + 0.9821i   0.5827 + 0.8127i   0.0551 - 0.9985i
   0.0000 + 1.0000i  -0.3924 + 0.9198i   0.9985 + 0.0551i  -0.7418 + 0.6706i  -0.9455 + 0.3257i   0.6287 + 0.7776i  -0.9821 + 0.1883i  -0.9772 - 0.2122i   0.1340 + 0.9910i
  -1.0000 + 0.0000i  -0.3257 - 0.9455i  -0.9910 + 0.1340i  -0.6706 - 0.7418i   0.4830 - 0.8756i  -0.7639 - 0.6453i  -0.1883 - 0.9821i   0.8672 - 0.4979i  -0.3182 - 0.9480i
  -1.0000 + 0.0000i  -1.0000 + 0.0000i  -1.0000 + 0.0000i   0.1006 - 0.9949i   0.1006 - 0.9949i   0.1006 - 0.9949i   0.9291 - 0.3699i   0.9291 - 0.3699i   0.9291 - 0.3699i
  -0.0000 - 1.0000i   0.7418 - 0.6706i   0.9821 - 0.1883i   0.9949 + 0.1006i   0.5925 + 0.8056i   0.0885 + 0.9961i   0.3699 + 0.9291i  -0.4412 + 0.8974i  -0.8428 + 0.5383i
   1.0000 - 0.0000i  -0.1006 + 0.9949i  -0.9291 + 0.3699i  -0.1006 + 0.9949i  -0.9797 - 0.2003i  -0.2745 - 0.9616i  -0.9291 + 0.3699i  -0.2745 - 0.9616i   0.7263 - 0.6874i
   0.0000 + 1.0000i  -0.5925 - 0.8056i   0.8428 - 0.5383i  -0.9949 - 0.1006i   0.8611 - 0.5084i   0.4507 + 0.8927i  -0.3699 - 0.9291i   0.8485 + 0.5292i  -0.5839 + 0.8118i
  -1.0000 + 0.0000i   0.9797 + 0.2003i  -0.7263 + 0.6874i   0.1006 - 0.9949i  -0.2978 + 0.9546i  -0.6108 - 0.7918i   0.9291 - 0.3699i  -0.9843 + 0.1764i   0.4205 - 0.9073i
  -0.0000 - 1.0000i  -0.8611 + 0.5084i   0.5839 - 0.8118i   0.9949 + 0.1006i  -0.4192 - 0.9079i   0.7490 + 0.6626i   0.3699 + 0.9291i   0.6119 - 0.7909i  -0.2421 + 0.9702i
   1.0000 - 0.0000i   0.2978 - 0.9546i  -0.4205 + 0.9073i  -0.1006 + 0.9949i   0.9198 + 0.3924i  -0.8604 - 0.5097i  -0.9291 + 0.3699i   0.0764 + 0.9971i   0.0551 - 0.9985i
   0.0000 + 1.0000i   0.4192 + 0.9079i   0.2421 - 0.9702i  -0.9949 - 0.1006i  -0.9455 + 0.3257i   0.9409 + 0.3386i  -0.3699 - 0.9291i  -0.7253 - 0.6884i   0.1340 + 0.9910i
  -1.0000 + 0.0000i  -0.9198 - 0.3924i  -0.0551 + 0.9985i   0.1006 - 0.9949i   0.4830 - 0.8756i  -0.9879 - 0.1553i   0.9291 - 0.3699i   0.9997 + 0.0243i  -0.3182 - 0.9480i
  -0.0000 - 1.0000i   0.9455 - 0.3257i  -0.1340 - 0.9910i   0.9949 + 0.1006i   0.2289 + 0.9735i   0.9994 - 0.0335i   0.3699 + 0.9291i  -0.7579 + 0.6523i   0.4910 + 0.8711i
  -0.0000 - 1.0000i  -0.0000 - 1.0000i  -0.0000 - 1.0000i   0.5925 + 0.8056i   0.5925 + 0.8056i   0.5925 + 0.8056i  -0.8428 + 0.5383i  -0.8428 + 0.5383i  -0.8428 + 0.5383i
   1.0000 - 0.0000i   0.6706 + 0.7418i   0.1883 + 0.9821i  -0.8056 + 0.5925i  -0.9797 - 0.2003i  -0.7336 - 0.6796i  -0.5383 - 0.8428i   0.2642 - 0.9645i   0.7263 - 0.6874i
   0.0000 + 1.0000i  -0.9949 - 0.1006i  -0.3699 - 0.9291i  -0.5925 - 0.8056i   0.8611 - 0.5084i   0.8485 + 0.5292i   0.8428 - 0.5383i   0.4507 + 0.8927i  -0.5839 + 0.8118i
  -1.0000 + 0.0000i   0.8056 - 0.5925i   0.5383 + 0.8428i   0.8056 - 0.5925i  -0.2978 + 0.9546i  -0.9330 - 0.3600i   0.5383 + 0.8428i  -0.9330 - 0.3600i   0.4205 - 0.9073i
  -0.0000 - 1.0000i  -0.2003 + 0.9797i  -0.6874 - 0.7263i   0.5925 + 0.8056i  -0.4192 - 0.9079i   0.9841 + 0.1778i  -0.8428 + 0.5383i   0.9335 - 0.3586i  -0.2421 + 0.9702i
   1.0000 - 0.0000i  -0.5084 - 0.8611i   0.8118 + 0.5839i  -0.8056 + 0.5925i   0.9198 + 0.3924i  -0.9999 + 0.0107i  -0.5383 - 0.8428i  -0.4520 + 0.8920i   0.0551 - 0.9985i
   0.0000 + 1.0000i   0.9546 + 0.2978i  -0.9073 - 0.4205i  -0.5925 - 0.8056i  -0.9455 + 0.3257i   0.9800 - 0.1988i   0.8428 - 0.5383i  -0.2628 - 0.9648i   0.1340 + 0.9910i
  -1.0000 + 0.0000i  -0.9079 + 0.4192i   0.9702 + 0.2421i   0.8056 - 0.5925i   0.4830 - 0.8756i  -0.9251 + 0.3798i   0.5383 + 0.8428i   0.8420 + 0.5395i  -0.3182 - 0.9480i
  -0.0000 - 1.0000i   0.3924 - 0.9198i  -0.9985 - 0.0551i   0.5925 + 0.8056i   0.2289 + 0.9735i   0.8370 - 0.5473i  -0.8428 + 0.5383i  -0.9864 + 0.1644i   0.4910 + 0.8711i
   1.0000 - 0.0000i   0.3257 + 0.9455i   0.9910 - 0.1340i  -0.8056 + 0.5925i  -0.8226 - 0.5686i  -0.7189 + 0.6951i  -0.5383 - 0.8428i   0.6215 - 0.7834i  -0.6463 - 0.7631i

size(C)

ans = 1×2

40 9

[Sadiq Akbar]

Thank you dear Cris LaPierre for your response. No you didn't take my point. I was saying that I want to make the response of the 1st code like that of 2nd. You tried but that is not according to my question. I wanted to make the response of 1st code like that of 2nd and I did that myself with several trial and errors. Thank you once again