How to resolve the Error using ==> mtimes Inner matrix dimensions must agree?

% Magnitude spectrum computation (as column vectors)
MAG = abs( fft(frames,nfft,1) ); 

% Triangular filterbank with uniformly spaced filters on mel scale
H = trifbank( M, K, R, fs, hz2mel, mel2hz ); % size of H is M x K 

% Filterbank application to unique part of the magnitude spectrum
FBE = H*MAG(1:K,:); % FBE( FBE<1.0 ) = 1.0; % apply mel floor

Error using ==> mtimes
Inner matrix dimensions must agree.

Error in ==> new at 41
    FBE = H*MAG(1:K,:); % FBE( FBE<1.0 ) = 1.0; % apply mel floor

[Walter Roberson]

At the command line please give the command

dbstop if error

and then run your program again. When it stops at the error, please show

size(H)
size(MAG)
M
K

[Anurag Pujari]

It shows the following: 23 2049

         256        1534

M = 20 K =129

[Walter Roberson]

The code H*MAG(1:K,:) is assuming that the second dimension of H should be length K, but clearly it is not.

trifbank is not a built-in MATLAB routine. Did you download one of the implementations from the File Exchange? If so then you are going to have to debug why it is not returning matrices of width K.