wenergy (Wavelet Toolbox)

Energy for 1-D wavelet or wavelet packet decomposition

Syntax

```
[Ea,Ed] = WENERGY(C,L)
E = WENERGY(T)
```

Description

For a one-dimensional wavelet decomposition [C,L] (see wavedec for details), [Ea,Ed] = WENERGY(C,L) returns Ea, which is the percentage of energy corresponding to the approximation and Ed, which is the vector containing the percentages of energy corresponding to the details.

For a wavelet packet tree T (see wptree, wpdec, wpdec2), E = WENERGY(T) returns a vector E, which contains the percentages of energy corresponding to the terminal nodes of the tree T. In this case, WENERGY is a method of the wptree object T, which overloads the previous WENERGY function.

Examples

% Example 1: 1-D wavelet decomposition
%-------------------------------------
load noisbump
[C,L] = wavedec(noisbump,4,'sym4');
[Ea,Ed] = wenergy(C,L)

Ea =

   88.2860

Ed =

    2.1560    1.2286    1.4664    6.8630

% Example 2: 1-D wavelet packet decomposition
%--------------------------------------------
load noisbump
T = wpdec(noisbump,3,'sym4');
E = wenergy(T)

E =

95.0329    1.4664    0.6100    0.6408    0.5935    0.5445    0.5154    
0.5965

wdencmp wenergy2