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25
26## -*- texinfo -*-
27## @deftypefn  {} {} line ()
28## @deftypefnx {} {} line (@var{x}, @var{y})
29## @deftypefnx {} {} line (@var{x}, @var{y}, @var{z})
30## @deftypefnx {} {} line ("xdata", @var{x}, "ydata", @var{y})
31## @deftypefnx {} {} line ("xdata", @var{x}, "ydata", @var{y}, "zdata", @var{z})
32## @deftypefnx {} {} line (@dots{}, @var{property}, @var{value})
33## @deftypefnx {} {} line (@var{hax}, @dots{})
34## @deftypefnx {} {@var{h} =} line (@dots{})
35## Create a line object from @var{x} and @var{y} (and possibly @var{z}) and
36## insert it in the current axes.
37##
38## In the standard calling form the data @var{x}, @var{y}, and @var{z} may be
39## scalars, vectors, or matrices.  In the case of matrix inputs, @code{line}
40## will attempt to orient scalars and vectors so the results can be plotted.
41## This requires that one of the dimensions of the vector match either the
42## number of rows or the number of columns of the matrix.
43##
44## In the low-level calling form (50% higher performance) where the data is
45## specified by name (@code{line ("xdata", @var{x}, @dots{})}) the data must be
46## vectors.  If no data is specified (@code{line ()}) then
47## @w{@code{@var{x} == @var{y} = [0, 1]}}.
48##
49## Multiple property-value pairs may be specified for the line object, but they
50## must appear in pairs.
51##
52## If called with only @var{property}/@var{value} pairs then any unspecified
53## properties use their default values as specified on the root object.
54##
55## If the first argument @var{hax} is an axes handle, then plot into this axes,
56## rather than the current axes returned by @code{gca}.
57##
58## The optional return value @var{h} is a graphics handle (or vector of
59## handles) to the line objects created.
60##
61## Programming Note: The full list of properties is documented at
62## @ref{Line Properties}.
63##
64## The function @code{line} differs from @code{plot} in that line objects are
65## inserted in to the current axes without first clearing the plot.
66## @seealso{image, patch, rectangle, surface, text}
67## @end deftypefn
68
69function h = line (varargin)
70
71  ## Get axis argument which may be in a 'parent' PROP/VAL pair
72  [hax, varargin] = __plt_get_axis_arg__ ("line", varargin{:});
73
74  if (isempty (hax))
75    hax = gca ();
76    oldfig = [];
77  else
78    hax = hax(1);
79    oldfig = get (0, "currentfigure");
80    set (0, "currentfigure", ancestor (hax, "figure"));
81  endif
82
83  unwind_protect
84    htmp = __line__ (hax, varargin{:});
85  unwind_protect_cleanup
86    if (! isempty (oldfig))
87      set (0, "currentfigure", oldfig);
88    endif
89  end_unwind_protect
90
91  if (nargout > 0)
92    h = htmp;
93  endif
94
95endfunction
96
97
98%!demo
99%! clf;
100%! line ([0 1], [0.8 0.8], "linestyle", "-", "color", "b");
101%! line ([0 1], [0.6 0.6], "linestyle", "--", "color", "g");
102%! line ([0 1], [0.4 0.4], "linestyle", ":", "color", "r");
103%! line ([0 1], [0.2 0.2], "linestyle", "-.", "color", "k");
104%! ylim ([0 1]);
105%! title ("line() with various linestyles");
106%! legend ('"-"', '"--"', '":"', '"-."', 'location', 'eastoutside');
107
108%!demo
109%! clf;
110%! x = 0:0.3:10;
111%! y1 = cos (x);
112%! y2 = sin (x);
113%! subplot (3,1,1);
114%!  args = {"color", "b", "marker", "s"};
115%!  line ([x(:), x(:)], [y1(:), y2(:)], args{:});
116%!  title ("Test broadcasting for line()");
117%! subplot (3,1,2);
118%!  line (x(:), [y1(:), y2(:)], args{:});
119%! subplot (3,1,3);
120%!  line ([x(:), x(:)+pi/2], y1(:), args{:});
121%!  xlim ([0 10]);
122
123%!test
124%! hf = figure ("visible", "off");
125%! unwind_protect
126%!   h = line;
127%!   assert (findobj (hf, "type", "line"), h);
128%!   assert (get (h, "xdata"), [0 1], eps);
129%!   assert (get (h, "ydata"), [0 1], eps);
130%!   assert (get (h, "type"), "line");
131%!   assert (get (h, "color"), get (0, "defaultlinecolor"));
132%!   assert (get (h, "linestyle"), get (0, "defaultlinelinestyle"));
133%!   assert (get (h, "linewidth"), get (0, "defaultlinelinewidth"), eps);
134%! unwind_protect_cleanup
135%!   close (hf);
136%! end_unwind_protect
137