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%ZEROPHASE Discrete-time filter zero-phase response. % [Hr,W] = ZEROPHASE(Hd,N) returns length N vectors Hr and W containing % the zero-phase response of the discrete-time filter Hd, and the % frequencies (in radians) at which it is evaluated. The zero-phase % response is evaluated at N points equally spaced around the upper half % of the unit circle. For an FIR filter where N is a power of two, the % computation is done faster using FFTs. If you don't specify N, it % defaults to 8192. % % [Hr,W] = ZEROPHASE(Hd) returns a matrix Hr if Hd is a vector. Each % column of the matrix corresponds to each filter in the vector. If a % row vector of frequency points is specified, each row of the matrix % corresponds to each filter in the vector. % % For additional parameters, see SIGNAL/ZEROPHASE. % Author: V. Pellissier, J. Schickler % Copyright 1988-2002 The MathWorks, Inc. % Help for the p-coded ZEROPHASE method of DFILT classes.