Group: Mathematical Functions
Subgroup: Fourier and Wavelet transforms
See also: fwtin invfwtin dwt invdwt fwt invfwt

Links:
Wavelet tutorial

Function: fwtinshift
Description: fwtinshift retrieves the wavelet coefficients for a given shift of the Fast Wavelet Transformation of all circular shifts (fwtin) of a vector.

Usage: x = fwtinshift (ti, param)
Input:
ti n x d matrix, all circular shifts (fwtin)
param 2 x 1 vector, param[1] = log2(# of father wavelet coeffs), param[2] = shift
Output:
x n x 1 vector, resulting coefficients

Notes:
ti can be retrieved by fwtin. n has to be a power of 2. 2^d gives the number of coefficients for the father wavelets.

Example:
library ("wavelet") 
x  = (0:15)/16 
y  = sin(pi*x)+normal(16) 
ti = fwtin (y, 2, daubechies4) 
fwtinshift (ti, cols(ti)|0) 

Result:
reproduces x since no shifts were done. 




Group: Mathematical Functions
Subgroup: Fourier and Wavelet transforms
See also: fwtin invfwtin dwt invdwt fwt invfwt

© XploRe, generated on 6.3.98 7:17 .