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

    %% CWT Coefficient Moduli and Maxima Lines
% Determine the local maxima from the CWT of the |cuspamax| signal
% using the default Morse wavelet. Plot the CWT coefficient moduli and
% maxima lines. 
load cuspamax;
%%
% Plot the |cuspamax| signal and notice the shape of the signal near
% samples 300 and 700. The signal shows a cusp near sample 700.
plot(cuspamax);
xlabel('Sample');
%%
% Plot the wavelet transform modulus maxima and note the local Holder
% exponent values at samples 308 and 717. 
wtmm(cuspamax,'ScalingExponent','local');
%%
% Holder exponent values indicate the strength of the singularities in a 
% signal. Signal locations where the local Holder exponent is 0 are 
% discontinuous at that location. Locations with Holder exponenets greater
% than or equal to 1 are differentiable. Holder exponent values less than 
% but close to 1 indicate that the signal at the location is almost 
% differentiable. The closer the Holder exponent value is to 0, the stronger
% the singularity. 
%%
% The Holder exponent at sample 308 is 1.9  and at sample 717 is 0.39. The 
% low Holder value at sample 717 confirms that the signal is not 
% differentiable and has a fairly strong singularity at that point.