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25
26## -*- texinfo -*-
27## @deftypefn {} {@var{deg} =} rad2deg (@var{rad})
28##
29## Convert radians to degrees.
30##
31## The input @var{rad} must be a scalar, vector, or N-dimensional array of
32## double or single floating point values.  @var{rad} may be complex in which
33## case the real and imaginary components are converted separately.
34##
35## The output @var{deg} is the same size and shape as @var{rad} with radians
36## converted to degrees using the conversion constant @code{180/pi}.
37##
38## Example:
39##
40## @example
41## @group
42## rad2deg ([0, pi/2, pi, 3/2*pi, 2*pi])
43##   @result{}  0    90   180   270   360
44## @end group
45## @end example
46## @seealso{deg2rad}
47## @end deftypefn
48
49function deg = rad2deg (rad)
50
51  if (nargin != 1)
52    print_usage ();
53  endif
54
55  if (! isfloat (rad))
56    error ("rad2deg: RAD must be a floating point class (double or single)");
57  endif
58
59  deg = rad * (180/pi);
60
61endfunction
62
63
64%!assert (rad2deg (0), 0)
65%!assert (rad2deg (pi/2), 90)
66%!assert (rad2deg (pi), 180)
67%!assert (rad2deg (pi*[0, 1/2, 1, 3/2, 2]), [0, 90, 180, 270, 360])
68
69## Test input validation
70%!error rad2deg ()
71%!error rad2deg (1, 2)
72%!error <RAD must be a floating point class> rad2deg (uint8 (1))
73%!error <RAD must be a floating point class> rad2deg ("A")
74