fftdiff.m

Jump to: navigation, search

Spectral differentiation kernel. Differentiation corresponds to multiplication in the Fourier domain. This function generates the multiplier.

Syntax

    kern=fftdiff(order,npoints,dx)


Arguments

      order   - order of the derivative

npoints - number of points in the grid

dx      - grid step length


Outputs

      kern - a vector that is to be used for accurate
numerical differentiation of periodic real
signals in the following way:

derivative=real(ifft(fft(signal).*kern));


Notes

Periodic boundary conditions.

See also

Version 2.1, authors: Ilya Kuprov