1######################################################################## 2## 3## Copyright (C) 2008-2021 The Octave Project Developers 4## 5## See the file COPYRIGHT.md in the top-level directory of this 6## distribution or <https://octave.org/copyright/>. 7## 8## This file is part of Octave. 9## 10## Octave is free software: you can redistribute it and/or modify it 11## under the terms of the GNU General Public License as published by 12## the Free Software Foundation, either version 3 of the License, or 13## (at your option) any later version. 14## 15## Octave is distributed in the hope that it will be useful, but 16## WITHOUT ANY WARRANTY; without even the implied warranty of 17## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18## GNU General Public License for more details. 19## 20## You should have received a copy of the GNU General Public License 21## along with Octave; see the file COPYING. If not, see 22## <https://www.gnu.org/licenses/>. 23## 24######################################################################## 25 26## -*- texinfo -*- 27## @deftypefn {} {} realsqrt (@var{x}) 28## Return the real-valued square root of each element of @var{x}. 29## 30## If any element results in a complex return value @code{realsqrt} aborts and 31## issues an error. 32## @seealso{sqrt, realpow, reallog} 33## @end deftypefn 34 35function y = realsqrt (x) 36 37 if (nargin != 1) 38 print_usage (); 39 elseif (iscomplex (x) || any (x(:) < 0)) 40 error ("realsqrt: produced complex result"); 41 else 42 y = sqrt (x); 43 endif 44 45endfunction 46 47 48%!assert (realsqrt (1:5), sqrt (1:5)) 49%!test 50%! x = rand (10, 10); 51%! assert (realsqrt (x), sqrt (x)); 52 53%!error realsqrt () 54%!error realsqrt (1,2) 55%!error <produced complex result> realsqrt (-1) 56