buttord

(/tools/hpmatlab/toolbox/signal/buttord.m)

Function Synopsis

[order,wn] = buttord(wp,ws,rp,rs,opt)

Help text

BUTTORD Butterworth filter order selection.
	[N, Wn] = BUTTORD(Wp, Ws, Rp, Rs) returns the order N of the
	lowest order digital Butterworth filter that loses no more than
	Rp dB in the passband and has at least Rs dB of attenuation
	in the stopband.  The passband runs from 0 to Wp and the
	stopband extends from Ws to 1.0, the Nyquist frequency.
	BUTTORD also returns Wn, the Butterworth natural frequency (or, 
	the "3 dB frequency") to use with BUTTER to achieve the specifications. 
	[N, Wn] = BUTTORD(Wp, Ws, Rp, Rs, 's') does the computation
	for an analog filter.

	When Rp is chosen as 3 dB, the Wn in BUTTER is equal to Wp
	in BUTTORD.  

	See also BUTTER, CHEB1ORD, CHEB2ORD, and ELLIPORD.

Cross-Reference Information

abs            /tools/hpmatlab/toolbox/matlab/elfun/abs.m
atan           /tools/hpmatlab/toolbox/matlab/elfun/atan.m
ceil           /tools/hpmatlab/toolbox/matlab/elfun/ceil.m
else           /tools/hpmatlab/toolbox/matlab/lang/else.m
elseif         /tools/hpmatlab/toolbox/matlab/lang/elseif.m
end            /tools/hpmatlab/toolbox/matlab/lang/end.m
error          /tools/hpmatlab/toolbox/matlab/lang/error.m
for            /tools/hpmatlab/toolbox/matlab/lang/for.m
if             /tools/hpmatlab/toolbox/matlab/lang/if.m
length         /tools/hpmatlab/toolbox/matlab/general/length.m
log10          /tools/hpmatlab/toolbox/matlab/elfun/log10.m
min            /tools/hpmatlab/toolbox/matlab/datafun/min.m
nargin         /tools/hpmatlab/toolbox/matlab/elmat/nargin.m
pi             /tools/hpmatlab/toolbox/matlab/elmat/pi.m
sort           /tools/hpmatlab/toolbox/matlab/datafun/sort.m
sqrt           /tools/hpmatlab/toolbox/matlab/elfun/sqrt.m
tan            /tools/hpmatlab/toolbox/matlab/elfun/tan.m

filtdemo       /tools/hpmatlab/toolbox/signal/filtdemo.m