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view scripts/general/nextpow2.m @ 27981:7f1cec12c240
maint: Remove simple "Adapted-By:" lines from code base.
* __ftp__.cc, urlwrite.cc, lin2mu.m, mu2lin.m, bincoeff.m, common_size.m,
nextpow2.m, shift.m, xor.m, griddata.m, colormap.m, gray.m, gray2ind.m,
image.m, imagesc.m, imshow.m, ind2gray.m, ind2rgb.m, ocean.m, rgb2ind.m,
findstr.m, commutation_matrix.m, cross.m, gls.m, isdefinite.m, ishermitian.m,
issymmetric.m, null.m, ols.m, orth.m, qzhess.m, vech.m, orderfields.m, untar.m,
unzip.m, orient.m, __pltopt__.m, __gnuplot_print__.m, subplot.m, compan.m,
conv.m, deconv.m, poly.m, polyder.m, polyfit.m, polyint.m, polyreduce.m,
polyval.m, polyvalm.m, residue.m, roots.m, detrend.m, fftconv.m, fftfilt.m,
fftshift.m, ifftshift.m, beta.m, lcm.m, pow2.m, corr.m, kurtosis.m, skewness.m,
base2dec.m, bin2dec.m, blanks.m, deblank.m, dec2base.m, dec2bin.m, dec2hex.m,
hex2dec.m, index.m, rindex.m, substr.m, calendar.m, datestr.m, datevec.m,
eomday.m, now.m, weekday.m:
Remove simple "Adapted-By:" lines from code base.
author | Rik <rik@octave.org> |
---|---|
date | Tue, 21 Jan 2020 13:15:15 -0800 |
parents | bdad8ca48700 |
children | 9f9ac219896d |
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######################################################################## ## ## Copyright (C) 1995-2020 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{n} =} nextpow2 (@var{x}) ## Compute the exponent for the smallest power of two larger than the input. ## ## For each element in the input array @var{x}, return the first integer ## @var{n} such that ## @tex ## $2^n \ge |x|$. ## @end tex ## @ifnottex ## 2^n @geq{} abs (x). ## @end ifnottex ## ## @seealso{pow2, log2} ## @end deftypefn ## Author: KH <Kurt.Hornik@wu-wien.ac.at> function n = nextpow2 (x) if (nargin != 1) print_usage (); endif if (! isnumeric (x)) error ("nextpow2: X must be numeric"); endif [f, n] = log2 (abs (x)); idx = (n == 0); # Find any failures of log2 function (n == 0) n(idx) = f(idx); # and copy over value. n(f == 0.5)--; endfunction %!assert (nextpow2 (16), 4) %!assert (nextpow2 (17), 5) %!assert (nextpow2 (31), 5) %!assert (nextpow2 (-16), 4) %!assert (nextpow2 (-17), 5) %!assert (nextpow2 (-31), 5) %!assert (nextpow2 (1:17), [0 1 2 2 3 3 3 3 4 4 4 4 4 4 4 4 5]) ## Special cases %!assert (nextpow2 (0), 0) %!assert (nextpow2 (1), 0) %!assert (nextpow2 (Inf), Inf) %!assert (nextpow2 (-Inf), Inf) %!assert (nextpow2 (NaN), NaN) %!assert (nextpow2 ([1, Inf, 3, -Inf, 9, NaN]), [0, Inf, 2, Inf, 4, NaN]) ## Test input validation %!error nexpow2 () %!error nexpow2 (1, 2) %!error <X must be numeric> nextpow2 ("t")