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## AST_POLYCURVE - Draw a series of connected geodesic curves

Description:
This routine joins a series of points specified in the physical coordinate system of a Plot by drawing a sequence of geodesic curves. It is equivalent to making repeated calls to the AST_CURVE routine (q.v.), except that AST_POLYCURVE will generally be more efficient when drawing many geodesic curves end-to-end. A typical application of this might be in drawing contour lines.

As with AST_CURVE, full account is taken of the Mapping between physical and graphical coordinate systems. This includes any discontinuities and clipping established using AST_CLIP.

Invocation:
CALL AST_POLYCURVE( THIS, NPOINT, NCOORD, INDIM, IN, STATUS )
Arguments:
THIS = INTEGER (Given)
Pointer to the Plot.
NPOINT = INTEGER (Given)
The number of points between which geodesic curves are to be drawn.
NCOORD = INTEGER (Given)
The number of coordinates being supplied for each point (i.e. the number of axes in the current Frame of the Plot, as given by its Naxes attribute).
INDIM = INTEGER (Given)
The number of elements along the first dimension of the IN array (which contains the input 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 NPOINT.
IN( INDIM, NCOORD ) = DOUBLE PRECISION (Given)
A 2-dimensional array giving the physical coordinates of the points which are to be joined in sequence by geodesic curves. These should be stored such that the value of coordinate number COORD for input point number POINT is found in element IN(POINT,COORD).
STATUS = INTEGER (Given and Returned)
The global status.
Notes:
• No curve is drawn on either side of any point which has any coordinate equal to the value AST__BAD.

• 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: AST_POLYGON - Create a Polygon
Up: AST Routine Descriptions
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AST A Library for Handling World Coordinate Systems in Astronomy