Mercurial > octave
view scripts/specfun/realpow.m @ 30947:fe898ae23e0e stable
betainc.m: Use sophisticated technique for calculating exponents to avoid innacuracies (bug #62329)
* betainc.m: Use expm1() and log1p() to replace exponentiation operator ".^" in
special case code when a or b equals 1. Add BIST tests for bug #62329.
author | Nir Krakauer <nkrakauer@ccny.cuny.edu> |
---|---|
date | Tue, 19 Apr 2022 15:09:27 -0700 |
parents | 796f54d4ddbf |
children | 5d3faba0342e |
line wrap: on
line source
######################################################################## ## ## Copyright (C) 2008-2022 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 {} {} realpow (@var{x}, @var{y}) ## Compute the real-valued, element-by-element power operator. ## ## This is equivalent to @w{@code{@var{x} .^ @var{y}}}, except that ## @code{realpow} reports an error if any return value is complex. ## @seealso{power, reallog, realsqrt} ## @end deftypefn function z = realpow (x, y) if (nargin != 2) print_usage (); endif z = x .^ y; if (iscomplex (z)) error ("realpow: produced complex result"); endif endfunction %!assert (realpow (1:10, 0.5:0.5:5), power (1:10, 0.5:0.5:5)) %!assert (realpow (1:10, 0.5:0.5:5), [1:10] .^ [0.5:0.5:5]) %!test %! x = rand (10, 10); %! y = randn (10, 10); %! assert (x.^y, realpow (x,y)); %!assert <47775> (realpow (1i,2), -1) %!error <Invalid call> realpow () %!error <Invalid call> realpow (1) %!error <produced complex result> realpow (-1, 1/2)