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Change multisignal 1-D decomposition coefficients


DEC = chgwdeccfs(DEC,'ca',COEFS)
DEC = chgwdeccfs(DEC,'cd',COEFS,LEV)
DEC = chgwdeccfs(DEC,'all',CA,CD)
DEC = chgwdeccfs(DEC,'all',V)
DEC = chgwdeccfs(...,IDXSIG)


DEC = chgwdeccfs(DEC,'ca',COEFS) replaces the approximation coefficients at level DEC.level with those contained in the matrix COEFS. If COEFS is a single value V, all coefficients are replaced by V.

DEC = chgwdeccfs(DEC,'cd',COEFS,LEV) replaces the detail coefficients at level LEV with those contained in the matrix COEFS. If COEFS is a single value V, then LEV can be a vector of levels and all the coefficients that belong to these levels are replaced by V. LEV must be such that  LEV  DEC.level

DEC = chgwdeccfs(DEC,'all',CA,CD) replaces all the approximation and detail coefficients. CA must be a matrix and CD must be a cell array of length DEC.level.

If COEFS (or CA or CD) is a single number, then it replaces all the related coefficients. Otherwise, COEFS (or CA, or CD) must be a matrix of appropriate size.

For a real value V, DEC = chgwdeccfs(DEC,'all',V) replaces all the coefficients by V.

DEC = chgwdeccfs(...,IDXSIG) replaces the coefficients for the signals whose indices are given by the vector IDXSIG. If the initial data are stored row-wise or column-wise in a matrix X, then IDXSIG contains the row or column indices, respectively, of the data.


% Load original 1D-multisignal
load thinker

% Perform a decomposition at level 2 using wavelet db2
dec = mdwtdec('r',X,2,'db2');

% Change the coefficients of details at level 1.
% Replace all values by 0.
decBIS = chgwdeccfs(dec,'cd',0,1);

% Change the coefficients of details at level 1 and 
% level 2 for signals 31 to 35. Replace all values by 0.
decTER = chgwdeccfs(dec,'cd',0,1:2,31:35);

% Compare original and new coefficients for details
% at level 1 for signals 31 to 35.
plot({1}(31:35,:)','b'); hold on;

See Also


Introduced in R2007a

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