www.gusucode.com > signal 工具箱matlab源码程序 > signal/@dfilt/@abstractsos/thisislinphase.m
function f = thisislinphase(Hd,tol) %THISISLINPHASE True for linear phase filter. % THISISLINPHASE(Hd) returns 1 if filter Hd is linear phase, and 0 otherwise. % % THISISLINPHASE(Hd,TOL) uses tolerance TOL to determine when two numbers are % close enough to be considered equal. % % See also DFILT. % Copyright 1988-2012 The MathWorks, Inc. if nargin < 2 tol=[]; end warnsv(Hd); [b,a] = tf(Hd); f = islinphase(b,a,tol);