wdatamgr (Wavelet Toolbox)

Manager for data structure.

[OUT1,OUT2] = wdatamgr(O,D,IN3,IN4,IN5)

Description

wdatamgr is a tree management utility.

[OUT1,OUT2] = wdatamgr(O,D,IN3,IN4,IN5) where D is the data structure and O is a string option. The possible options are:

'write_cfs': writes coefficients for a terminal node
data = wdatamgr('write_cfs',data,tree,node,coefs);

'read_cfs': reads coefficients for a terminal node
coefs = wdatamgr('read_cfs',data,tree,node);

'read_ent': reads the entropy vector
ent = wdatamgr('read_ent',data,nodes);

'read_ento': reads the optimal entropy vector
ento = wdatamgr('read_ento',data,nodes);

'read_tp_ent': reads the type and the parameter for entropy
[type_ent,param] = wdatamgr('read_tp_ent',data);

'read_wave': reads the name of the wavelet
wave = wdatamgr('read_wave',data);

Examples

% Load signal. 
    load noisdopp; x = noisdopp;

% Decompose x at depth 3 with db1 wavelet packets 
% using Shannon entropy. 
    [t,d] = wpdec(x,3,'db1','shannon');

% Read entropy name. 
    ent_name = wdatamgr('read_tp_ent',d) 
ent_name =
shannon

% Read wavelet name. 
    wav_name = wdatamgr('read_wave',d) 
wav_name =
db1
% Read packet (3,2) coefficients. 
    cfs = wdatamgr('read_cfs',d,t,[3 2]);

% Read packet (3,2) entropy and optimal entropy. 
    ind_node = depo2ind(2,[3 2]); 
    ent = wdatamgr('read_ent',d,ind_node)
ent =
-318.4298

% Optimal entropy is NaN because no optimization has been done. 
    ento = wdatamgr('read_ento',d,ind_node)
ento =
NaN

% Modify packet (3,2) coefficients. 
    ncfs = cos(cfs);     % or any other modification !

% Update packet (3,2) coefficients. 
    d = wdatamgr('write_cfs',d,t,[3 2],ncfs);

% Update nodes entropy. 
    d = entrupd(t,d,'shannon'); 
    nent = wdatamgr('read_ent',d,ind_node)
nent =
22.2830