how does Wenergy for 1-D wavelet decomposition works???

Hi , i read the matlab documentation about the energy for 1-D wavelet decomposition and i want to know how the calculation works exactly??? because the Syntax used is [Ea,Ed] = wenergy(C,L) so here it use the wavelet decomposition vector c and the formula used in theory is

Which use the details and approximations coefficients . can anyone help me to understand please??

Answer 1

[Wayne King]

Hi Alef, the Ed output gives the percentage of energy captured by the detail (wavelet) coefficients at each level, while the Ea output is the coarsest scale (final-level) scaling coefficient energy (again as a percentage).

load noisbump;
% 4 levels here
[C,L] = wavedec(noisbump,4,'sym4');
[Ea,Ed] = wenergy(C,L);

Ed is 1-by-4, the percent energy captured by the wavelet coefficients from the finest scale to coarsest scale.

Ea is a scalar representing the final-scale scaling coefficient energy.

[Leandro Robaina Arla]

Hi, i don´t understand completely.

Is this the answer?

Ed=(Energy of detail 1,Energy of detail 2, Energy of detail 3, Energy of detail 4).

or is the inverse

Ed=(Energy of detail 4,Energy of detail 3, Energy of detail 2, Energy of detail 1).

thank you for the help