www.gusucode.com > wavelet工具箱matlab源码程序 > wavelet/wavelet/cwtftinfo.m
function cwtftinfo %CWTFTINFO Information on wavelets for CWTFT % CWTFTINFO provides information on the available wavelets for % Continuous Wavelet Transform using FFT. % % PSI_HAT denotes the Fourier transform of the wavelet. % % Morlet: % 'morl': % PSI_HAT(k) = pi^(-1/4)exp(-(k-k0)^2/2)H(k) where H(k) is the % Heaviside function. % Parameter: k0, default k0 = 6. % k0 is the center frequency in radians/sample. The center frequency % cycles/sample is k0/(2*pi). % % 'morlex': (without Heaviside function) % PSI_HAT(k) = pi^(-1/4)exp(-(k-k0)^2/2) % Parameter: k0, default k0 = 6. % k0 is the center frequency in radians/sample. The center frequency % in cycles/sample is k0/(2*pi). % % 'morl0': (with exact zero mean value) % PSI_HAT(k) = pi^(-1/4) [exp(-(k-k0)^2/2) - exp(k0^2/2)] % Parameter: k0, default k0 = 6. % k0 is the center frequency in % radians/sample. The center frequency in cycles/sample is % k0/(2*pi). % % DOG: % 'dog': m order Derivative Of Gaussian % PSI_HAT(k) = -(i^m/sqrt(gamma(m+0.5)))(k^m)exp(-k^2/2) % Parameter: m (order of derivative), default m = 2. The order % m must be even. % sqrt(m+1/2) is the approximate center frequency in radians/sample. % The center frequency cycles/sample is sqrt(m+1/2)/(2*pi). % % 'mexh': % PSI_HAT(k) = (1/gamma(2+0.5))k^2 exp(-k^2/2) % (DOG wavelet with m = 2) % sqrt(5/2) is the approximate center frequency in radians/sample. % The center frequency is cycles/sample is sqrt(5/2)/(2*pi). % % Paul: % 'paul': % PSI_HAT(k) = (2^m)/sqrt(m(2*m-1)!)k^m exp(-k) Parameter: m, % default m = 4. m+1/2 is the approximate center frequency in % radians/sample. (m+1/2)/(2*pi) is the center frequency % in cycles/sample. % % Bump: % 'bump' % PSI_HAT(k) = exp(1-(1/(1-(k-mu)^2/sigma^2)))(abs((k-mu)/sigma)<1) % Parameters: mu,sigma. default: mu=5, sigma = 0.6. % Allowable parameter ranges: 3 <= mu <= 6 % 0.1 < sigma <1.2 % Note that mu-sigma is strictly positive. % mu is the center frequency in radians/sample. The center frequency % in cycles/sample is mu/(2*pi). % % % % See also CWTFT, CWT, ICWTFT. % M. Misiti, Y. Misiti, G. Oppenheim, J.M. Poggi 04-Mar-2010. % Copyright 1995-2015 The MathWorks, Inc. help cwtftinfo