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coordsys.toworld - Function

	Package	general
	Module	images
	Tool	coordsys

Convert from absolute pixel coordinate to world

Synopsis
toworld(value, format)

Arguments

value	in	Absolute pixel coordinate
		Allowed:	Numeric vector
		Default:	Reference pixel
format	in	Format string
		Allowed:	String from combination of "n", "q", "s", "m"
		Default:	'n'

Returns
Vector numeric, vector quantity, vector string, record, or fail

Description

This function converts between absolute pixel coordinate (1-rel) and absolute world (physical coordinate).

If you supply fewer pixel values than there are axes in the Coordinate System, your coordinate vector will be padded out with the reference pixel for the missing axes. Excess values will be silently ignored.

You may ask for the world coordinate in all of the formats described in the discussion regarding the formatting possibilities available via argument format.

Example

- cs := coordsys(direction=T, spectral=T)
-
- cs.toworld([-2,2,2], 'n')
[3.00000051 1.00000001 1.415001e+09]       
-
- cs.toworld([-2,2,2], 'q')
[*1=[value=3.00000051, unit='], 
 *2=[value=1.00000001, unit='], 
 *3=[value=1.415001e+09, unit=Hz]] 
-
- cs.toworld([-2,2,2], 'm')
[direction=[type=direction, refer=J2000, m1=[value=0.000290888213, unit=rad],  
                                         m0=[unit=rad, value=0.000872664774]], 
 spectral=[frequency=[type=frequency, refer=LSRK, m0=[value=1.415001e+09, unit=Hz]], 
           radiovelocity=[value=1140.73308, unit=km/s], 
           opticalvelocity=[value=1145.09023, unit=km/s], 
           betavelocity=[value=1142.90335, unit=km/s]]] 
-
- cs.toworld([-2,2,2], 's')
00:00:12.000 +00.01.00.000 1.415001e+09

Example

- cs := coordsys (stokes="I V", linear=2)
- cs.toworld([1,2,3], 's')
I 1.000000e+00 2.000000e+00 
-
- cs.toworld([1,2,3], 'm')
[stokes=I, linear=[*1=[value=1, unit=km], *2=[value=2, unit=km]]] 
-
- cs.toworld([1,2,3], 'q')
[*1=[value=1, unit=], *2=[value=1, unit=km], *3=[value=2, unit=km]]

Example

- cs := coordsys (spectral=T, linear=1)
- cs.toworld([1,2,3], 'q')
[*1=[value=1.415e+09, unit=Hz], *2=[value=1, unit=km]]