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Energy for 1-D wavelet or wavelet packet decomposition


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


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.


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

Ea =


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
Introduced before R2006a