mexihat (Wavelet Toolbox)

Mexican hat wavelet.

[PSI,X] = mexihat(LB,UB,N)

Description

[PSI,X] = mexihat(LB,UB,N) returns values of the Mexican hat wavelet on an N point regular grid, X, on the interval [LB,UB].

Output arguments are the wavelet function psi computed on the grid X, and the grid X.

This wavelet has [-5 5] as effective support.

This function is proportional to the second derivative function of the Gaussian probability density function.

Examples

% Set effective support and grid parameters. 
    lb = -5; ub = 5; n = 1000; 

% Compute and plot Mexican hat wavelet. 
    [psi,x] = mexihat(lb,ub,n); 
    plot(x,psi), title('Mexican hat wavelet')