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25
26## -*- texinfo -*-
27## @deftypefn {} {} realpow (@var{x}, @var{y})
28## Compute the real-valued, element-by-element power operator.
29##
30## This is equivalent to @w{@code{@var{x} .^ @var{y}}}, except that
31## @code{realpow} reports an error if any return value is complex.
32## @seealso{power, reallog, realsqrt}
33## @end deftypefn
34
35function z = realpow (x, y)
36
37  if (nargin != 2)
38    print_usage ();
39  endif
40
41  z = x .^ y;
42  if (iscomplex (z))
43    error ("realpow: produced complex result");
44  endif
45
46endfunction
47
48
49%!assert (realpow (1:10, 0.5:0.5:5), power (1:10, 0.5:0.5:5))
50%!assert (realpow (1:10, 0.5:0.5:5), [1:10] .^ [0.5:0.5:5])
51%!test
52%! x = rand (10, 10);
53%! y = randn (10, 10);
54%! assert (x.^y, realpow (x,y));
55%!assert <47775> (realpow (1i,2), -1)
56
57%!error realpow ()
58%!error realpow (1)
59%!error realpow (1,2,3)
60%!error <produced complex result> realpow (-1, 1/2)
61