Mercurial > octave
view scripts/signal/unwrap.m @ 30564:796f54d4ddbf stable
update Octave Project Developers copyright for the new year
In files that have the "Octave Project Developers" copyright notice,
update for 2021.
In all .txi and .texi files except gpl.txi and gpl.texi in the
doc/liboctave and doc/interpreter directories, change the copyright
to "Octave Project Developers", the same as used for other source
files. Update copyright notices for 2022 (not done since 2019). For
gpl.txi and gpl.texi, change the copyright notice to be "Free Software
Foundation, Inc." and leave the date at 2007 only because this file
only contains the text of the GPL, not anything created by the Octave
Project Developers.
Add Paul Thomas to contributors.in.
author | John W. Eaton <jwe@octave.org> |
---|---|
date | Tue, 28 Dec 2021 18:22:40 -0500 |
parents | 7854d5752dd2 |
children | 597f3ee61a48 |
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######################################################################## ## ## Copyright (C) 2000-2022 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## This file is part of Octave. ## ## Octave is free software: you can redistribute it and/or modify it ## under the terms of the GNU General Public License as published by ## the Free Software Foundation, either version 3 of the License, or ## (at your option) any later version. ## ## Octave is distributed in the hope that it will be useful, but ## WITHOUT ANY WARRANTY; without even the implied warranty of ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ## GNU General Public License for more details. ## ## You should have received a copy of the GNU General Public License ## along with Octave; see the file COPYING. If not, see ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {@var{b} =} unwrap (@var{x}) ## @deftypefnx {} {@var{b} =} unwrap (@var{x}, @var{tol}) ## @deftypefnx {} {@var{b} =} unwrap (@var{x}, @var{tol}, @var{dim}) ## ## Unwrap radian phases by adding or subtracting multiples of 2*pi as ## appropriate to remove jumps greater than @var{tol}. ## ## @var{tol} defaults to pi. ## ## Unwrap will work along the dimension @var{dim}. If @var{dim} ## is unspecified it defaults to the first non-singleton dimension. ## @end deftypefn function retval = unwrap (x, tol, dim) if (nargin < 1) print_usage (); endif if (! isnumeric (x)) error ("unwrap: X must be a numeric matrix or vector"); endif if (nargin < 2 || isempty (tol)) tol = pi; endif ## Don't let anyone use a negative value for TOL. tol = abs (tol); nd = ndims (x); sz = size (x); if (nargin == 3) if (!(isscalar (dim) && dim == fix (dim)) || !(1 <= dim && dim <= nd)) error ("unwrap: DIM must be an integer and a valid dimension"); endif else ## Find the first non-singleton dimension. (dim = find (sz > 1, 1)) || (dim = 1); endif rng = 2*pi; m = sz(dim); ## Handle case where we are trying to unwrap a scalar, or only have ## one sample in the specified dimension. if (m == 1) retval = x; return; endif ## Take first order difference to see so that wraps will show up ## as large values, and the sign will show direction. idx = repmat ({':'}, nd, 1); idx{dim} = [1,1:m-1]; d = x(idx{:}) - x; ## Find only the peaks, and multiply them by the appropriate amount ## of ranges so that there are kronecker deltas at each wrap point ## multiplied by the appropriate amount of range values. p = round (abs (d)./rng) .* rng .* (((d > tol) > 0) - ((d < -tol) > 0)); ## Now need to "integrate" this so that the deltas become steps. r = cumsum (p, dim); ## Now add the "steps" to the original data and put output in the ## same shape as originally. retval = x + r; endfunction %!shared i, t, r, w, tol %! i = 0; %! t = []; %! r = [0:100]; ## original vector %! w = r - 2*pi*floor ((r+pi)/(2*pi)); ## wrapped into [-pi,pi] %! tol = 1e3*eps; %!assert (r, unwrap (w), tol) %!assert (r', unwrap (w'), tol) %!assert ([r',r'], unwrap ([w',w']), tol) %!assert ([r; r ], unwrap ([w; w ], [], 2), tol) %!assert (r + 10, unwrap (10 + w), tol) %!assert (w', unwrap (w', [], 2)) %!assert (w, unwrap (w, [], 1)) %!assert ([w; w], unwrap ([w; w])) ## Test that small values of tol have the same effect as tol = pi %!assert (r, unwrap (w, 0.1), tol) %!assert (r, unwrap (w, eps), tol) ## Test that phase changes larger than 2*pi unwrap properly %!assert ([0; 1], unwrap ([0; 1])) %!assert ([0; 4 - 2*pi], unwrap ([0; 4])) %!assert ([0; 7 - 2*pi], unwrap ([0; 7])) %!assert ([0; 10 - 4*pi], unwrap ([0; 10])) %!assert ([0; 13 - 4*pi], unwrap ([0; 13])) %!assert ([0; 16 - 6*pi], unwrap ([0; 16])) %!assert ([0; 19 - 6*pi], unwrap ([0; 19])) %!assert (max (abs (diff (unwrap (100*pi * rand (1000, 1))))) < pi) %!test %! A = [pi*(-4), pi*(-2+1/6), pi/4, pi*(2+1/3), pi*(4+1/2), pi*(8+2/3), pi*(16+1), pi*(32+3/2), pi*64]; %! assert (unwrap (A), unwrap (A, pi)); %! assert (unwrap (A, pi), unwrap (A, pi, 2)); %! assert (unwrap (A', pi), unwrap (A', pi, 1)); %!test %! A = [pi*(-4); pi*(2+1/3); pi*(16+1)]; %! B = [pi*(-2+1/6); pi*(4+1/2); pi*(32+3/2)]; %! C = [pi/4; pi*(8+2/3); pi*64]; %! D = [pi*(-2+1/6); pi*(2+1/3); pi*(8+2/3)]; %! E(:, :, 1) = [A, B, C, D]; %! E(:, :, 2) = [A+B, B+C, C+D, D+A]; %! F(:, :, 1) = [unwrap(A), unwrap(B), unwrap(C), unwrap(D)]; %! F(:, :, 2) = [unwrap(A+B), unwrap(B+C), unwrap(C+D), unwrap(D+A)]; %! assert (unwrap (E), F); %!test %! A = [0, 2*pi, 4*pi, 8*pi, 16*pi, 65536*pi]; %! B = [pi*(-2+1/6), pi/4, pi*(2+1/3), pi*(4+1/2), pi*(8+2/3), pi*(16+1), pi*(32+3/2), pi*64]; %! assert (unwrap (A), zeros (1, length (A))); %! assert (diff (unwrap (B), 1) < 2*pi, true (1, length (B)-1)); ## Test input validation %!error <Invalid call> unwrap () %!error unwrap ("foo")