Group: | Mathematical Functions |
Topic: | Fourier and Wavelet transforms |
See also: | invfwt dwt invdwt fwtin fwtinshift fwt2 |
Function: | fwt | |
Description: | fwt computes the Fast Wavelet Transformation of a vector. |
Usage: | {a, b} = fwt (x, l, h) | |
Input: | ||
x | n x 1 vector, input data where n has to be a power of 2 | |
l | integer, number of father wavelet coefficients | |
h | m x 1 vector, wavelet basis | |
Output: | ||
a | l x 2 matrix, indices and coefficients of the father wavelets | |
b | (n-l) x 3 matrix, indices and coefficients of the mother wavelets |
library ("wavelet") x = (0:1023)/1023 {a, b} = fwt (x, 4, daubechies4) a b
Contents of a [1,] 0 0.079014 [2,] 1 0.20414 [3,] 2 0.33734 [4,] 3 0.3795 Contents of b [ 1,] 1 0 -0.11404 [ 2,] 1 1 -4.9204e-17 [ 3,] 1 2 -3.5032e-17 [ 4,] 1 3 0.030175 [ 5,] 2 0 -0.080708 [ 6,] 2 1 -1.5787e-17 [ 7,] 2 2 -1.2105e-17 [ 8,] 2 3 -3.6657e-17 ... [ 676,] 8 167 -1.2086e-18 [ 677,] 8 168 -1.1804e-18 [ 678,] 8 169 -1.369e-18 [ 679,] 8 170 -9.0717e-19 [ 680,] 8 171 -1.0957e-18 [ 681,] 8 172 -1.2844e-18 [ 682,] 8 173 -8.2247e-19 [ 683,] 8 174
Group: | Mathematical Functions |
Topic: | Fourier and Wavelet transforms |
See also: | invfwt dwt invdwt fwtin fwtinshift fwt2 |