octave-nkf: scripts/signal/freqz.m annotate

annotate scripts/signal/freqz.m @ 20266:83792dd9bcc1

Use in-place operators in m-files where possible. * scripts/audio/@audioplayer/set.m, scripts/audio/@audiorecorder/set.m, scripts/audio/mu2lin.m, scripts/elfun/cosd.m, scripts/general/del2.m, scripts/general/profexplore.m, scripts/general/quadl.m, scripts/general/rat.m, scripts/general/rotdim.m, scripts/help/get_first_help_sentence.m, scripts/help/private/__strip_html_tags__.m, scripts/image/cubehelix.m, scripts/io/textread.m, scripts/linear-algebra/duplication_matrix.m, scripts/linear-algebra/housh.m, scripts/linear-algebra/krylov.m, scripts/linear-algebra/logm.m, scripts/linear-algebra/normest.m, scripts/linear-algebra/onenormest.m, scripts/optimization/fminsearch.m, scripts/optimization/lsqnonneg.m, scripts/optimization/qp.m, scripts/plot/appearance/annotation.m, scripts/plot/appearance/axis.m, scripts/plot/appearance/legend.m, scripts/plot/appearance/specular.m, scripts/plot/draw/colorbar.m, scripts/plot/draw/hist.m, scripts/plot/draw/plotmatrix.m, scripts/plot/draw/private/__stem__.m, scripts/plot/util/__actual_axis_position__.m, scripts/plot/util/__gnuplot_drawnow__.m, scripts/plot/util/findobj.m, scripts/plot/util/print.m, scripts/plot/util/private/__go_draw_axes__.m, scripts/plot/util/private/__print_parse_opts__.m, scripts/plot/util/rotate.m, scripts/polynomial/pchip.m, scripts/polynomial/polyaffine.m, scripts/polynomial/polyder.m, scripts/polynomial/private/__splinefit__.m, scripts/polynomial/residue.m, scripts/signal/arch_fit.m, scripts/signal/arch_rnd.m, scripts/signal/bartlett.m, scripts/signal/blackman.m, scripts/signal/freqz.m, scripts/signal/hamming.m, scripts/signal/hanning.m, scripts/signal/spectral_adf.m, scripts/signal/spectral_xdf.m, scripts/signal/stft.m, scripts/sparse/bicgstab.m, scripts/sparse/cgs.m, scripts/sparse/private/__sprand_impl__.m, scripts/sparse/qmr.m, scripts/sparse/sprandsym.m, scripts/sparse/svds.m, scripts/specfun/legendre.m, scripts/special-matrix/gallery.m, scripts/statistics/base/gls.m, scripts/statistics/models/logistic_regression.m, scripts/statistics/tests/kruskal_wallis_test.m, scripts/statistics/tests/manova.m, scripts/statistics/tests/wilcoxon_test.m, scripts/time/datevec.m: Use in-place operators in m-files where possible.

author	Rik <rik@octave.org>
date	Tue, 26 May 2015 21:07:42 -0700
parents	f1d0f506ee78
children

rev	line source
19731 4197fc428c7d maint: Update copyright notices for 2015. John W. Eaton <jwe@octave.org> parents: 19723 diff changeset	1 ## Copyright (C) 1994-2015 John W. Eaton
2313 5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	2 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	3 ## This file is part of Octave.
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	4 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	5 ## Octave is free software; you can redistribute it and/or modify it
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	6 ## under the terms of the GNU General Public License as published by
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6653 diff changeset	7 ## the Free Software Foundation; either version 3 of the License, or (at
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6653 diff changeset	8 ## your option) any later version.
2313 5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	9 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	10 ## Octave is distributed in the hope that it will be useful, but
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	13 ## General Public License for more details.
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	14 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2311 diff changeset	15 ## You should have received a copy of the GNU General Public License
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6653 diff changeset	16 ## along with Octave; see the file COPYING. If not, see
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6653 diff changeset	17 ## <http://www.gnu.org/licenses/>.
2303 5cffc4b8de57 [project @ 1996-06-24 09:15:24 by jwe] jwe parents: 1337 diff changeset	18
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	19 ## -- texinfo --
16491 b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	20 ## @deftypefn {Function File} {[@var{h}, @var{w}] =} freqz (@var{b}, @var{a}, @var{n}, "whole")
18453 9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	21 ## @deftypefnx {Function File} {[@var{h}, @var{w}] =} freqz (@var{b})
9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	22 ## @deftypefnx {Function File} {[@var{h}, @var{w}] =} freqz (@var{b}, @var{a})
9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	23 ## @deftypefnx {Function File} {[@var{h}, @var{w}] =} freqz (@var{b}, @var{a}, @var{n})
16489 36dba9be680b doc: Make documentation compatible with Texinfo 5.0 (bug #38392) Amod Mulay <amodmulay1@gmail.com> parents: 14363 diff changeset	24 ## @deftypefnx {Function File} {@var{h} =} freqz (@var{b}, @var{a}, @var{w})
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	25 ## @deftypefnx {Function File} {[@var{h}, @var{w}] =} freqz (@dots{}, @var{Fs})
16489 36dba9be680b doc: Make documentation compatible with Texinfo 5.0 (bug #38392) Amod Mulay <amodmulay1@gmail.com> parents: 14363 diff changeset	26 ## @deftypefnx {Function File} {} freqz (@dots{})
19627 446c46af4b42 strip trailing whitespace from most source files John W. Eaton <jwe@octave.org> parents: 18453 diff changeset	27 ##
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	28 ## Return the complex frequency response @var{h} of the rational IIR filter
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	29 ## whose numerator and denominator coefficients are @var{b} and @var{a},
20200 f1d0f506ee78 doc: Update more docstrings to have one sentence summary as first line. Rik <rik@octave.org> parents: 19867 diff changeset	30 ## respectively.
f1d0f506ee78 doc: Update more docstrings to have one sentence summary as first line. Rik <rik@octave.org> parents: 19867 diff changeset	31 ##
f1d0f506ee78 doc: Update more docstrings to have one sentence summary as first line. Rik <rik@octave.org> parents: 19867 diff changeset	32 ## The response is evaluated at @var{n} angular frequencies between 0 and
8517 81d6ab3ac93c Allow documentation tobe built for other formats than tex and info sh@sh-laptop parents: 8506 diff changeset	33 ## @ifnottex
18453 9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	34 ## 2*pi.
8517 81d6ab3ac93c Allow documentation tobe built for other formats than tex and info sh@sh-laptop parents: 8506 diff changeset	35 ## @end ifnottex
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	36 ## @tex
18453 9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	37 ## $2\pi$.
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	38 ## @end tex
3426 f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe] jwe parents: 3367 diff changeset	39 ##
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	40 ## @noindent
0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	41 ## The output value @var{w} is a vector of the frequencies.
3426 f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe] jwe parents: 3367 diff changeset	42 ##
16491 b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	43 ## If @var{a} is omitted, the denominator is assumed to be 1 (this
b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	44 ## corresponds to a simple FIR filter).
b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	45 ##
20200 f1d0f506ee78 doc: Update more docstrings to have one sentence summary as first line. Rik <rik@octave.org> parents: 19867 diff changeset	46 ## If @var{n} is omitted, a value of 512 is assumed. For fastest computation,
f1d0f506ee78 doc: Update more docstrings to have one sentence summary as first line. Rik <rik@octave.org> parents: 19867 diff changeset	47 ## @var{n} should factor into a small number of small primes.
16491 b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	48 ##
17281 bc924baa2c4e doc: Add new @qcode macro for code samples which are quoted. Rik <rik@octave.org> parents: 16491 diff changeset	49 ## If the fourth argument, @qcode{"whole"}, is omitted the response is
bc924baa2c4e doc: Add new @qcode macro for code samples which are quoted. Rik <rik@octave.org> parents: 16491 diff changeset	50 ## evaluated at frequencies between 0 and
8517 81d6ab3ac93c Allow documentation tobe built for other formats than tex and info sh@sh-laptop parents: 8506 diff changeset	51 ## @ifnottex
18453 9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	52 ## pi.
8517 81d6ab3ac93c Allow documentation tobe built for other formats than tex and info sh@sh-laptop parents: 8506 diff changeset	53 ## @end ifnottex
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	54 ## @tex
18453 9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	55 ## $\pi$.
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	56 ## @end tex
3426 f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe] jwe parents: 3367 diff changeset	57 ##
16491 b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	58 ## @code{freqz (@var{b}, @var{a}, @var{w})}
3426 f8dde1807dee [project @ 2000-01-13 08:40:00 by jwe] jwe parents: 3367 diff changeset	59 ##
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	60 ## Evaluate the response at the specific frequencies in the vector @var{w}.
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	61 ## The values for @var{w} are measured in radians.
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	62 ##
16489 36dba9be680b doc: Make documentation compatible with Texinfo 5.0 (bug #38392) Amod Mulay <amodmulay1@gmail.com> parents: 14363 diff changeset	63 ## @code{[@dots{}] = freqz (@dots{}, @var{Fs})}
16491 b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	64 ##
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	65 ## Return frequencies in Hz instead of radians assuming a sampling rate
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	66 ## @var{Fs}. If you are evaluating the response at specific frequencies
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	67 ## @var{w}, those frequencies should be requested in Hz rather than radians.
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	68 ##
16489 36dba9be680b doc: Make documentation compatible with Texinfo 5.0 (bug #38392) Amod Mulay <amodmulay1@gmail.com> parents: 14363 diff changeset	69 ## @code{freqz (@dots{})}
16491 b10a23fe80bb doc: Tweak docstrings of functions changed for Texinfo 5.0 compatibility. Rik <rik@octave.org> parents: 16489 diff changeset	70 ##
18453 9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	71 ## Plot the magnitude and phase response of @var{h} rather than returning them.
9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	72 ##
9d59bc3dc12d doc: Update docstrings for freqz, freqz_plot. Rik <rik@octave.org> parents: 18450 diff changeset	73 ## @seealso{freqz_plot}
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	74 ## @end deftypefn
904 3470f1e25a79 [project @ 1994-11-09 21:22:15 by jwe] jwe parents: 566 diff changeset	75
3367 0748b03c3510 [project @ 1999-11-20 14:52:38 by jwe] jwe parents: 2847 diff changeset	76 ## Author: jwe ???
2314 949ab8eba8bc [project @ 1996-07-12 03:58:02 by jwe] jwe parents: 2313 diff changeset	77
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	78 function [h_r, f_r] = freqz (b, a, n, region, Fs)
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	79
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	80 if (nargin < 1 \|\| nargin > 5)
6046 34f96dd5441b [project @ 2006-10-10 16:10:25 by jwe] jwe parents: 5986 diff changeset	81 print_usage ();
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	82 elseif (nargin == 1)
2303 5cffc4b8de57 [project @ 1996-06-24 09:15:24 by jwe] jwe parents: 1337 diff changeset	83 ## Response of an FIR filter.
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	84 a = n = region = Fs = [];
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	85 elseif (nargin == 2)
2303 5cffc4b8de57 [project @ 1996-06-24 09:15:24 by jwe] jwe parents: 1337 diff changeset	86 ## Response of an IIR filter
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	87 n = region = Fs = [];
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	88 elseif (nargin == 3)
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	89 region = Fs = [];
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	90 elseif (nargin == 4)
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	91 Fs = [];
5443 ec8c33dcd1bf [project @ 2005-09-08 01:40:57 by jwe] jwe parents: 5378 diff changeset	92 if (! ischar (region) && ! isempty (region))
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	93 Fs = region;
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	94 region = [];
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	95 endif
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	96 endif
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	97
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	98 if (isempty (b))
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	99 b = 1;
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	100 elseif (! isvector (b))
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	101 error ("freqz: B must be a vector");
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	102 endif
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	103 if (isempty (a))
c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	104 a = 1;
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	105 elseif (! isvector (a))
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	106 error ("freqz: A must be a vector");
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	107 endif
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	108 if (isempty (n))
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	109 n = 512;
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	110 elseif (isscalar (n) && n < 1)
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	111 error ("freqz: N must be a positive integer");
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	112 endif
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	113 if (isempty (region))
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	114 if (isreal (b) && isreal (a))
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	115 region = "half";
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	116 else
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	117 region = "whole";
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	118 endif
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	119 endif
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	120 if (isempty (Fs))
18450 694e8f0b3862 freqz: Make frequency response plot visually compatible with Matlab (bug #41464) Mike Miller <mtmiller@ieee.org> parents: 17744 diff changeset	121 freq_norm = true;
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	122 if (nargout == 0)
c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	123 Fs = 2;
c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	124 else
c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	125 Fs = 2*pi;
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	126 endif
18450 694e8f0b3862 freqz: Make frequency response plot visually compatible with Matlab (bug #41464) Mike Miller <mtmiller@ieee.org> parents: 17744 diff changeset	127 else
694e8f0b3862 freqz: Make frequency response plot visually compatible with Matlab (bug #41464) Mike Miller <mtmiller@ieee.org> parents: 17744 diff changeset	128 freq_norm = false;
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	129 endif
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	130 plot_output = (nargout == 0);
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	131 whole_region = strcmp (region, "whole");
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	132
5583 8eebdcfde94e [project @ 2005-12-15 01:16:26 by jwe] jwe parents: 5443 diff changeset	133 a = a(:);
8eebdcfde94e [project @ 2005-12-15 01:16:26 by jwe] jwe parents: 5443 diff changeset	134 b = b(:);
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	135
8506 bc982528de11 comment style fixes John W. Eaton <jwe@octave.org> parents: 7151 diff changeset	136 if (! isscalar (n))
bc982528de11 comment style fixes John W. Eaton <jwe@octave.org> parents: 7151 diff changeset	137 ## Explicit frequency vector given
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	138 w = f = n;
8506 bc982528de11 comment style fixes John W. Eaton <jwe@octave.org> parents: 7151 diff changeset	139 if (nargin == 4)
bc982528de11 comment style fixes John W. Eaton <jwe@octave.org> parents: 7151 diff changeset	140 ## Sampling rate Fs was specified
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	141 w = 2pif/Fs;
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	142 endif
5986 14078139f941 [project @ 2006-09-12 02:46:33 by jwe] jwe parents: 5583 diff changeset	143 k = max (length (b), length (a));
14078139f941 [project @ 2006-09-12 02:46:33 by jwe] jwe parents: 5583 diff changeset	144 hb = polyval (postpad (b, k), exp (j*w));
14078139f941 [project @ 2006-09-12 02:46:33 by jwe] jwe parents: 5583 diff changeset	145 ha = polyval (postpad (a, k), exp (j*w));
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	146 else
5583 8eebdcfde94e [project @ 2005-12-15 01:16:26 by jwe] jwe parents: 5443 diff changeset	147 ## polyval(fliplr(P),exp(jw)) is O(p n) and fft(x) is O(n log(n)),
6653 673686daec87 [project @ 2007-05-22 15:36:09 by jwe] jwe parents: 6046 diff changeset	148 ## where p is the order of the polynomial P. For small p it
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	149 ## would be faster to use polyval but in practice the overhead for
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	150 ## polyval is much higher and the little bit of time saved isn't
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	151 ## worth the extra code.
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	152 k = max (length (b), length (a));
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	153 if (k > n/2 && nargout == 0)
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	154 ## Ensure a causal phase response.
20266 83792dd9bcc1 Use in-place operators in m-files where possible. Rik <rik@octave.org> parents: 20200 diff changeset	155 n = 2 .^ ceil (log2 (2k/n));
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	156 endif
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	157
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	158 if (whole_region)
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	159 N = n;
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	160 if (plot_output)
19723 894b5c5e0b92 Add missing semicolon to cset 8724af455b11. Rik <rik@octave.org> parents: 19722 diff changeset	161 f = Fs * (0:n).' / N; # do 1 more for the plot
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	162 else
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	163 f = Fs * (0:n-1).' / N;
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	164 endif
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	165 else
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	166 N = 2*n;
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	167 if (plot_output)
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	168 n++;
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	169 endif
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	170 f = Fs * (0:n-1).' / N;
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	171 endif
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	172
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	173 pad_sz = N*ceil (k/N);
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	174 b = postpad (b, pad_sz);
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	175 a = postpad (a, pad_sz);
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	176
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	177 hb = zeros (n, 1);
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	178 ha = zeros (n, 1);
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	179
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	180 for i = 1:N:pad_sz
20266 83792dd9bcc1 Use in-place operators in m-files where possible. Rik <rik@octave.org> parents: 20200 diff changeset	181 hb += fft (postpad (b(i:i+N-1), N))(1:n);
83792dd9bcc1 Use in-place operators in m-files where possible. Rik <rik@octave.org> parents: 20200 diff changeset	182 ha += fft (postpad (a(i:i+N-1), N))(1:n);
8667 a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	183 endfor
a89198168175 freqz.m: freqz.m: fix for long input Ben Abbott <bpabbott@mac.com> parents: 8517 diff changeset	184
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	185 endif
8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	186
3893 abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	187 h = hb ./ ha;
abd8659eea11 [project @ 2002-04-09 21:36:31 by jwe] jwe parents: 3457 diff changeset	188
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	189 if (plot_output)
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	190 ## Plot and don't return values.
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	191 if (whole_region)
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	192 h(end+1) = h(1); # Solution is periodic. Copy first value to end.
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	193 endif
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	194 freqz_plot (f, h, freq_norm);
8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	195 else
8506 bc982528de11 comment style fixes John W. Eaton <jwe@octave.org> parents: 7151 diff changeset	196 ## Return values and don't plot.
3907 437884fae441 [project @ 2002-04-24 19:33:08 by jwe] jwe parents: 3893 diff changeset	197 h_r = h;
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	198 f_r = f;
7151 aeeb646f6538 [project @ 2007-11-09 19:34:17 by jwe] jwe parents: 7017 diff changeset	199 endif
3907 437884fae441 [project @ 2002-04-24 19:33:08 by jwe] jwe parents: 3893 diff changeset	200
566 8529a21443fa [project @ 1994-07-26 02:07:38 by jwe] jwe parents: diff changeset	201 endfunction
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	202
14363 f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	203
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	204 %!test # correct values and fft-polyval consistency
17336 b81b9d079515 Use '##' for comments which stand alone on a line. Rik <rik@octave.org> parents: 17281 diff changeset	205 %! ## butterworth filter, order 2, cutoff pi/2 radians
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	206 %! b = [0.292893218813452 0.585786437626905 0.292893218813452];
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	207 %! a = [1 0 0.171572875253810];
14363 f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	208 %! [h,w] = freqz (b,a,32);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	209 %! assert (h(1),1,10*eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	210 %! assert (abs (h(17)).^2,0.5,10*eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	211 %! assert (h,freqz (b,a,w),10*eps); # fft should be consistent with polyval
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	212
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	213 %!test # whole-half consistency
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	214 %! b = [1 1 1]/3; # 3-sample average
14363 f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	215 %! [h,w] = freqz (b,1,32,"whole");
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	216 %! assert (h(2:16),conj (h(32:-1:18)),20*eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	217 %! [h2,w2] = freqz (b,1,16,"half");
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	218 %! assert (h(1:16),h2,20*eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	219 %! assert (w(1:16),w2,20*eps);
5377 bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	220
bd4ee620c38a [project @ 2005-06-02 15:42:39 by jwe] jwe parents: 5307 diff changeset	221 %!test # Sampling frequency properly interpreted
5986 14078139f941 [project @ 2006-09-12 02:46:33 by jwe] jwe parents: 5583 diff changeset	222 %! b = [1 1 1]/3; a = [1 0.2];
14363 f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	223 %! [h,f] = freqz (b,a,16,320);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	224 %! assert (f,[0:15]'10,10eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	225 %! [h2,f2] = freqz (b,a,[0:15]*10,320);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	226 %! assert (f2,[0:15]10,10eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	227 %! assert (h,h2.',20*eps);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	228 %! [h3,f3] = freqz (b,a,32,"whole",320);
f3d52523cde1 Use Octave coding conventions in all m-file %!test blocks Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	229 %! assert (f3,[0:31]'10,10eps);
17338 1c89599167a6 maint: End m-files with 1 blank line. Rik <rik@octave.org> parents: 17336 diff changeset	230
19867 9fc020886ae9 maint: Clean up m-files to follow Octave coding conventions. Rik <rik@octave.org> parents: 19731 diff changeset	231 ## Test input validation
9fc020886ae9 maint: Clean up m-files to follow Octave coding conventions. Rik <rik@octave.org> parents: 19731 diff changeset	232 ## FIXME: Need to put tests here and simplify input validation in the main code.
19722 8724af455b11 freqz.m: Add 1 more point to the plot output (bug #438950). Doug Stewart <doug.dastew@gmail.com parents: 19627 diff changeset	233

Mercurial > octave-nkf

annotate scripts/signal/freqz.m @ 20266:83792dd9bcc1