CImage:DistanceWcsStr

The DistanceWcsStr method calculates the distance in WCS units between 2 image points measured in world coordinates and returns the result as a string. The related Distance method computes the Distance for pixel coordinates.

Syntax

sDistance = CImage:DistanceWcsStr( x1, y1, x2, y2)

where

x1,y1 are world coordinate values for the coordinate of the first point.

x2,y2 are world coordinate values for the coordinate of the first point.

sDistance is a string giving the wold coordinate distance (see below).

On success, this method returns sDistance.

On failure, this method returns nil

The DistanceWcsStr method returns a distance in world coordinate units as a string. Also see the related DistanceWcs method that returns the world coordinate calibrated distance as a number.

Example

Assume an image is displayed and attached to a CImageView named V. The following script measures the Distance between between two points (x1,y1) and (x2,y2) when the coordinates are in distance units (pixels, mm, microns, etc.):

I = V:GetImage()	-- load the image from a
x1 = 442.5 ; y1 = 220.44	-- point 1
x2 = 1.554 ; y2 = 20.552	-- point 2
sD = I:DistanceWcsStr(x1,y1,x2,y2)	-- make the measurement, returns a string

Alternatively, the following example supposes an astronomical image with an equatorial calibration and that the points are expressed in angular units:

V:GetImage()	-- load the image from a
x1 = "05:42:15.52" ; y1 = "20:40:12.5"	-- point 1
x2 = "05:42:44.12" ; y2 = "20:42:42.1"	-- point 2
sD = I:DistanceWcsStr(x1,y1,x2,y2)	-- make the measurement, returns a string