could anyone help me to overcome the error stating RESHAPE the number of elements must not change.

function [ rx_data ] = ofdm_rx( sym_seq, mod_ofdm ) 

N_data = mod_ofdm.FFTLength - sum(mod_ofdm.NumGuardBandCarriers) - 1 - length(mod_ofdm.PilotCarrierIndices); 
N_P = length(mod_ofdm.PilotCarrierIndices); 
num_ofdmsym = mod_ofdm.NumSymbols; 
 
pilot_seq_complex = rand (N_P, num_ofdmsym), rand (N_P, num_ofdmsym); 
sym_mat = reshape(sym_seq, N_data, num_ofdmsym); 

 
rx_data = step(mod_ofdm,sym_mat,pilot_seq_complex); 
 
end 

When i run the code containinf function i am getting error stating

Error using reshape
To RESHAPE the number of elements must not change.

Error in line 10 sym_mat = reshape(sym_seq, N_data, num_ofdmsym);

[jaah navi]

sym_seq_ofdma = reshape(sym_seq_ofdma_mat, numel(sym_seq_ofdma_mat), 1);

mod_ofdm_ofdma = comm.OFDMModulator(...

'FFTLength',N_ofdm,...

'NumGuardBandCarriers',N_GB,...

'PilotInputPort',true,...

'PilotCarrierIndices',N_P,...

'NumSymbols',num_ofdmsym_ofdma,...

'CyclicPrefixLength',N_ofdm*CP,...

'InsertDCNull',true);

this is the main code.

[Luna]

Could you please share the full information and all of your necessary inputs/outputs to run your code? If we can't run and simulate your code, we can't see what's going on.

I really don't understand where you call the ofdm_rx( sym_seq, mod_ofdm ) function.

I am getting below error for example, and I am sure I will get more errors since the other variables are not defined in my workspace.

Undefined function or variable 'sym_seq_ofdma_mat'.

[Image Analyst]

Luna, please put answers down BELOW in the official Answers section, so you can get credit for it. Your first comment looks pretty much like an answer to me.

[Luna]

Thanks, I moved the comment down as an answer :)

Answer 1

[Luna]

Actually the error gives you the hint. The number of elements inside the array should be equal to multiplication of dimensions.

For example:

A is MxN matrix, and you want to reshape it into PxR matrix. Then M*N should be equal to P*R. So that reshape function can work as follows:

newA = reshape(A,P,R);

What is sym_seq, mod_ofdm ? And what do you want as desired output?