I understand that you have a cell array consisting of three cells, each with dimensions of 868 by 16. After applying a level 6 discrete wavelet transform (DWT) using the 'db3' wavelet on each cell, are the dimensions of the resulting detail and approximation coefficients correctly corresponding to the original data cells?
Here's a corrected version of your code with comments explaining the changes:
dwt_coeffs_struct = struct('A', cell(size(data)), 'D', cell(size(data)));
for i = 1:numel(data)
% Convert the cell data to double and reshape it to a column vector
signal = reshape(cell2mat(data{i}), [], 1);
% Perform the DWT for 6 levels using 'db3' wavelet
[C, L] = wavedec(signal, 6, 'db3');
% Initialize arrays to store approximation coefficients and detail coefficients
A_coeffs = cell(1, 6);
D_coeffs = cell(1, 6);
% Extract approximation coefficients at level 6
A_coeffs{6} = appcoef(C, L, 'db3', 6);
% Extract detail coefficients for each level
for j = 1:6
D_coeffs{j} = detcoef(C, L, j);
end
% Store the DWT coefficients for this signal in the structure array
dwt_coeffs_struct(i).A = A_coeffs;
dwt_coeffs_struct(i).D = D_coeffs;
end
for i = 1:numel(data)
fprintf('Detail Coefficients for signal %d:\n', i);
for j = 1:6
fprintf('D%d: %d by 1\n', j, length(dwt_coeffs_struct(i).D{j}));
end
end
Key Corrections:
Signal Reshaping : Ensure that each cell's data is reshaped to a column vector before applying the DWT. This step is crucial to maintain the integrity of the signal.
Coefficient Storage: Store the approximation coefficients only at the highest level (level 6). Store detail coefficients for each level from 1 to 6.
Correct Usage of wavedec: The 'wavedec' function is correctly used to decompose the signal up to the specified level.
