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25
26## -*- texinfo -*-
27## @deftypefn {} {} blanks (@var{n})
28## Return a string of @var{n} blanks.
29##
30## For example:
31##
32## @example
33## @group
34## blanks (10);
35## whos ans
36##      @result{}
37##       Attr Name        Size                     Bytes  Class
38##       ==== ====        ====                     =====  =====
39##            ans         1x10                        10  char
40## @end group
41## @end example
42## @seealso{repmat}
43## @end deftypefn
44
45function s = blanks (n)
46
47  if (nargin != 1)
48    print_usage ();
49  elseif (! (isscalar (n) && n == fix (n) && n >= 0))
50    error ("blanks: N must be a non-negative integer");
51  endif
52
53  ## If 1:n is empty, the following expression will create an empty
54  ## character string.  Otherwise, it will create a row vector.
55  s(1:n) = " ";
56
57endfunction
58
59
60## There really isn't that much to test here
61%!assert (blanks (0), "")
62%!assert (blanks (5), "     ")
63%!assert (blanks (10), "          ")
64
65## Test input validation
66%!error blanks ()
67%!error blanks (1, 2)
68%!error blanks (ones (2))
69%!error blanks (2.1)
70%!error blanks (-2)
71