#### Description:

This function 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 use of the astCurve function (q.v.), except that astPolyCurve 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 astCurve, full account is taken of the Mapping between physical and graphical coordinate systems. This includes any discontinuities and clipping established using astClip.

#### Synopsis

void astPolyCurve( AstPlot ∗this, int npoint, int ncoord, int indim, const double ∗in )

#### Parameters:

##### this

Pointer to the Plot.

##### npoint

The number of points between which geodesic curves are to be drawn.

##### ncoord

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

The number of elements along the second 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

The address of the first element in a 2-dimensional array of shape `"` [ncoord][indim]`"` 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 point number `"` point`"` is found in element `"` in[coord][point]`"` .

#### 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).

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