[PHI,PSI,T] = meyer(LB,UB,
[PHI,PSI,T] = meyer(LB,UB, returns
Meyer scaling and wavelet functions evaluated on an
regular grid in the interval
N must be a power of two.
Output arguments are the scaling function
the wavelet function
PSI computed on the grid
These functions have [-8 8] as effective support.
If only one function is required, a fourth argument is allowed:
[PHI,T] = meyer(LB,UB,N,'phi') [PSI,T] = meyer(LB,UB,N,'psi')
When the fourth argument is used, but not equal to
outputs are the same as in the main option.
The Meyer wavelet and scaling function are defined in the frequency domain.
By changing the auxiliary function (see
meyeraux for more information), you
get a family of different wavelets.
% Set effective support and grid parameters. lb = -8; ub = 8; n = 1024; % Compute and plot Meyer wavelet and scaling functions. [phi,psi,x] = meyer(lb,ub,n); subplot(211), plot(x,psi) title('Meyer wavelet') subplot(212), plot(x,phi) title('Meyer scaling function')
Starting from an explicit form of the Fourier transform of ϕ,
the values of on a regular grid,
and then the values of ϕ are computed using
the inverse nonstandard discrete FFT.
The procedure for ψ is along the same lines.
Daubechies, I. (1992), Ten lectures on wavelets, CBMS-NSF conference series in applied mathematics, SIAM Ed., pp. 117–119, 137, 152.