www.gusucode.com > wavelet 源码程序 matlab案例代码 > wavelet/DetermineCenterFrequencyExample.m

    %% Determine Center Frequency
% This example shows how to determine the center frequency in hertz for
% Daubechies' least-asymmetric wavelet with 4 vanishing moments.

% Copyright 2015 The MathWorks, Inc.

cfreq = centfrq('sym4');
%%
% Obtain the wavelet and create a sine wave with a frequency equal to the
% center frequency, |cfreq|, of the wavelet. Use a starting phase of $-\pi$
% for the sine wave to visualize how the oscillation in the sine
% wave matches the oscillation in the wavelet.
[~,psi,xval] = wavefun('sym4');
y = cos(2*pi*cfreq*xval-pi);
plot(xval,psi,'linewidth',2); 
hold on;
plot(xval,y,'r');