functions in graph.i - c
closed= plotting keyword
or smooth= plotting keyword
selects closed curves (closed=1) or default open curves (closed=0),
or Bezier smoothing (smooth>0) or default piecewise linear curves
(smooth=0). The value of smooth can be 1, 2, 3, or 4 to get
successively more smoothing. Only the Bezier control points are
plotted to an X window; the actual Bezier curves will show up in
PostScript hardcopy files. Closed curves join correctly, which
becomes more noticeable for wide lines; non-solid closed curves
may look bad because the dashing pattern may be incommensurate
with the length of the curve.
PLOTTING COMMANDS: plg, plc (smooth only)
keyword, defined at i0/graph.i line 951
color= plotting keyword
selects line or text color. Valid values are the strings "bg", "fg",
"black", "white", "red", "green", "blue", "cyan", "magenta", "yellow",
or a 0-origin index into the current palette. The default is "fg".
Negative numbers may be used instead of the strings: -1 is bg
(background), -2 is fg (foreground), -3 is black, -4 is white,
-5 is red, -6 is green, -7 is blue, -8 is cyan, -9 is magenta, and
-10 is yellow. (The negative numbers are actually taken modulo
256, so -1 is also 255, -2 is 254, and so on.)
A color can also be a triple [r, g, b], with values running from
0 for dark to 255 for full intensity. Beware, however, of
specifying an rgb color (either as a color keyword or to the
plf, pli, or plfp commands) if your display is not a true color
display (for example, if it is 8 bits deep or less). In that
case, it may switch to a 5x9x5 color cube, which causes a
significant degradation in quality of rendering with smooth
color palettes. Furthermore, the hcp command will not work
properly for rgb colors if the file is a CGM. Use the rgb=1
keyword in the window command to avoid having to re-issue a
palette command after the first rgb object is drawn (this is
unnecessary on true color screens).
PLOTTING COMMANDS: plg, plm, plc, pldj, plt
keyword, defined at i0/graph.i line 849
or color_bar, levs, colors
Draw a color bar below the current coordinate system. If LEVS is
not specified uses plfc_levs (set by previous call to plfc). If
COLORS is specified, it should have one more value than LEVS,
otherwise equally spaced colors are chosen, or plfc_colors if
plfc_levs was used. With the vert=1 keyword the color bar appears
to the left of the current coordinate system (vert=0 is default).
By default, color_bar will attempt to label some of the color
interfaces. With the labs= keyword, you can force the labelling
algorithm as follows: labs=0 supresses all labels, labs=n forces
a label at every nth interface, labs=[i,n] forces a label at every
nth interface starting from interface i (0<=i<=numberof(LEVS)).
You can use the adjust= keyword to move the bar closer to (adjust<0)
or further from (adjust>0) the viewport, and the height= keyword to
set the height of any labels (default 14 points).
interpreted function, defined at i0/graph.i line 1648
nc= contour(yc,xc, level, z, y,x)
or nc= contour(yc,xc, level, z, y,x,ireg)
returns the points on the contour curve that would have been
plotted by plc. Z, Y, X, and IREG are as for plc, and the
triangle= and region= keywords are accepted and have the same
meaning as for plc. Unlike plc, the triangle array is an output
as well as an input to contour; if supplied it may be modified
to reflect any triangulations which were performed by contour.
LEVEL is a scalar z value to return the points at that contour
level. All such points lie on edges of the mesh. If a contour
curve closes, the final point is the same as the initial point
(i.e.- that point is included twice in the returned list).
LEVEL is a pair of z values [z0,z1] to return the points of
a set of polygons which outline the regions between the two
contour levels. These will include points on the mesh boundary
which lie between the levels, in addition to the edge points
for both levels. The polygons are closed, simply connected,
and will not contain more than about 4000 points (larger polygons
are split into pieces with a few points repeated where the pieces
YC and XC are the output points on the curve(s), or nil if there
are no points. On input, they must be simple variable references,
not expressions. The return value NC is a list of the lengths of
the polygons/polylines returned in (XC,YC), or nil if there are
none. numberof(XC)==numberof(YC)==sum(NC). For the level pair
case, YC, XC, and NC are ready to be used as inputs to plfp.
KEYWORDS: triangle, region
builtin function, documented at i0/graph.i line 392
returns the number of the current graphics window, or -1 if none.
builtin function, documented at i0/graph.i line 106