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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