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.