wptree (Wavelet Toolbox)

WPTREE constructor

Syntax

T = wptree(ORDER,DEPTH,X,WNAME,ENT_TYPE,ENT_PAR)
T = wptree(ORDER,DEPTH,X,WNAME)
T = wptree( ... ,USERDATA)

Description

T = wptree(ORDER,DEPTH,X,WNAME,ENT_TYPE,PARAMETER) returns a complete wavelet packet tree T.

ORDER is an integer representing the order of the tree (the number of "children" of each non terminal node). ORDER must be equal to 2 or 4.

If ORDER = 2, T is a WPTREE object corresponding to a wavelet packet decomposition of the vector (signal) X, at level DEPTH with a particular wavelet WNAME.

If ORDER = 4, T is a WPTREE object corresponding to a wavelet packet decomposition of the matrix (image) X, at level DEPTH with a particular wavelet WNAME.

ENT_TYPE is a string containing the entropy type and ENT_PAR is an optional parameter used for entropy computation ( see wentropy, wpdec or wpdec2 for more information).

T = wptree(ORDER,DEPTH,X,WNAME) is equivalent to T = wptree(ORDER,DEPTH,X,WNAME,'shannon')

With T = wptree(ORDER,DEPTH,X,WNAME,ENT_TYPE,ENT_PAR,USERDATA) you may set a userdata field.

The function wptree returns a WPTREE object.

For more information on object fields, see the get function or type

```
help wptree/get
```

Class WPTREE (Parent class: DTREE)

Fields

'dtree'
: DTREE parent object.

'wavInfo'
: Structure (wavelet information).

'entInfo'
: Structure (entropy information).

'`dtree`'	`:` DTREE parent object.
'`wavInfo`'	`:` Structure (wavelet information).
'`entInfo`'	`:` Structure (entropy information).

The wavelet information structure, 'wavInfo', contains

'wavName
: Wavelet name.

'Lo_D'
: Low Decomposition filter.

'Hi_D'
: High Decomposition filter.

'Lo_R'
: Low Reconstruction filter.

'Hi_R'
: High Reconstruction filter.

'wavName	`:` Wavelet name.
'Lo_D'	`:` Low Decomposition filter.
'Hi_D'	`:` High Decomposition filter.
'Lo_R'	`:` Low Reconstruction filter.
'Hi_R'	`:` High Reconstruction filter.

The entropy information structure, 'entInfo', contains

'entName'
: Entropy name.

'entPar'
: Entropy parameter.

'entName'	`:` Entropy name.
'entPar'	`:` Entropy parameter.

Fields from the DTREE parent object:

'allNI'
: All nodes information.

'`allNI`'	`:` All nodes information.

'allNI' is an array of size nbnode by 5, which contains

ind
: index.

size
: Size of data.

ent
: Entropy.

ento
: Optimal entropy.

ind	`:` index.
size	`:` Size of data.
ent	`:` Entropy.
ento	`:` Optimal entropy.

Each line is built based on the following scheme:

Examples

% Create a wavelet packet tree.
x = rand(1,512);
t = wptree(2,3,x,'db3');
t = wpjoin(t,[4;5]);

% Plot tree t4.
plot(t);

% Click the node (3,0), (see the plot function).

See Also
dtree, ntree

wpthcoef wpviewcf