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astMark
-
Draw a set of markers for a Plot
- Description:
- This function draws a set of markers (symbols) at positions
specified in the physical coordinate system of a Plot. The
positions are transformed into graphical coordinates to
determine where the markers should appear within the plotting
area.
- Synopsis:
- void astMark( AstPlot
this, int nmark, int ncoord, int indim,
const double
in, int type )
- Parameters:
-
this
-
Pointer to the Plot.
-
nmark
-
The number of markers to draw. This may be zero, in which
case nothing will be drawn.
-
ncoord
-
The number of coordinates being supplied for each mark
(i.e. the number of axes in the current Frame of the Plot, as
given by its Naxes attribute).
-
indim
-
The number of elements along the second dimension of the "in"
array (which contains the marker coordinates). This value is
required so that the coordinate values can be correctly
located if they do not entirely fill this array. The value
given should not be less than "nmark".
-
in
-
The address of the first element of a 2-dimensional array of
shape "[ncoord][indim]" giving the
physical coordinates of the points where markers are to be
drawn. These should be stored such that the value of
coordinate number "coord" for input mark number "mark" is
found in element "in[coord][mark]".
-
type
-
A value specifying the type (e.g. shape) of marker to be
drawn. The set of values which may be used (and the shapes
that will result) is determined by the underlying graphics
system.
- Notes:
- Markers are not drawn at positions which have any coordinate
equal to the value AST__BAD (or where the transformation into
graphical coordinates yields coordinates containing the value
AST__BAD).
- If any marker position is clipped (see astClip), then the
entire marker is not drawn.
- An error results if the base Frame of the Plot is not 2-dimensional.
- An error also results if the transformation between the
current and base Frames of the Plot is not defined (i.e. the
Plot's TranInverse attribute is zero).
Next: astMaskX - Mask a region of a data grid
Up: AST Function Descriptions
Previous: astMapType - Get the data type of an entry in a KeyMap
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk
Copyright (C) 2009 Science \& Technology Facilities Council