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coordsys.toabsmany - Function

	Package	general
	Module	images
	Tool	coordsys

Convert many numeric relative coordinates to absolute

Synopsis
toabsmany(value, isworld)

Arguments

value	in	Relative coordinates
		Allowed:	Numeric matrix
isworld	in	Is coordinate world or pixel ?
		Allowed:	T, F, unset
		Default:	unset

Returns
Numeric matrix or fail

Description

This function converts many relative coordinates to absolute. It exists so you can efficiently make many conversions (which would be rather slow if you did them all with toabs). Because speed is the object, the interface is purely in terms of numeric matrices, rather than being able to accept strings and quanta etc. like toabs can.

When dealing with world coordinates, the units of the numeric values must be the native units, given by function units.

Example

- cs := coordsys(direction=T, spectral=T)    # 3 axes
-
- rv := cs.referencevalue();                 # reference value
- w := cs.torel(rv)                          # make relative
- inc := cs.increment();                     # increment
- idx := 1:100;
- off := inc[3] * idx;                       # offset for third axis
- wrel := array (w, 3, 100);                 # 100 conversions each of length 3
- wrel[3,] +:= off;                          # Make spectral axis values change
-
- wabs  := cs.toabsmany (rel, T)             # Convert
- wabs[,1]                                   # First absolute coordinate
[0 0 1.415001e+09]  
- wabs[,100]                                 # 100th absolute coordinate
[0 0 1.415002e+09]

This example uses world coordinates.