FF = bwfilterf(F,FSIZE,ORDER) applies a lowpass Butterworth filter
to the vector/scalar field F with a cutoff size FSIZE (in grid units)
and order ORDER. F must be a square vector or scalar field; if it is
not square, bwfilterf first extracts the the central square of F (see
extractf). Typical values for FSIZE are around 1, and typical values
for ORDER are in the range 2-10.
FF = bwfilterf(F,FSIZE,ORDER,OPT), where OPT is a string that may
contain one or several substrings:
'low', 'high': specifies a lowpass (by default) or highpass filter
't': truncates the borders of width FSIZE, which are
affected by the filtering.
If no output argument, the result is displayed by showvec or showscal.
bwfilterf first Fourier transforms the field(s), low/high-pass
filters and inverse Fourier transformsF.
Note: A highpass filter of order ORDER is equivalent to a lowpass
filter of order -ORDER.
Example: showvec(bwfilterf(loadset,3,8));
F. Moisy
Revision: 1.10, Date: 2005/10/09
See Also
filterf, addnoisef, truncf, extractf.