Difference between revisions of "Fftdiff.m"
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| − | Spectral differentiation kernel. | + | Spectral differentiation kernel. Differentiation corresponds to multiplication in the Fourier domain. This function generates the multiplier. |
==Syntax== | ==Syntax== | ||
kern=fftdiff(order,npoints,dx) | kern=fftdiff(order,npoints,dx) | ||
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==Arguments== | ==Arguments== | ||
Revision as of 14:50, 16 August 2018
Spectral differentiation kernel. Differentiation corresponds to multiplication in the Fourier domain. This function generates the multiplier.
Contents
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
fdmat.m, fdvec.m, fourlap.m, fourdif.m
Version 2.1, authors: Ilya Kuprov
