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##### coordsys.convert - Function

1.1.3 Convert a numeric mixed coordinate

Description

This function converts between mixed pixel/world/abs/rel numeric coordinates. The input and output coordinates are specified via a numeric vector giving coordinate values, a string vector giving units, a boolean vector specifying whether the coordinate is absolute or relative (to the reference pixel) and doppler strings specifying the doppler convention for velocities.

The units string may include pix for pixel coordinates and velocity units (i.e. any unit consistent with m/s).

The allowed doppler strings and definition are described in function summary.

The shape argument is optional. If your Coordinate System is from an image, then assign the image shape to this argument. It is used only when making mixed (pixel/world) conversions for Direction Coordinates to resolve ambiguity.

The example clarifies the use of this function.

Arguments

 Inputs coordin Input coordinate, as a numeric vector allowed: doubleArray Default: absin Are input coordinate elements absolute ? allowed: boolArray Default: true dopplerin Input doppler type for velocities allowed: string Default: radio unitsin Input units, string vector allowed: stringArray Default: Native absout Are output coordinate elements absolute ? allowed: boolArray Default: true dopplerout Output doppler type for velocities allowed: string Default: radio unitsout Output units allowed: stringArray Default: Native shape Image shape, integer vector allowed: intArray Default: -1
Returns
doubleArray

Example

In this example we convert from a vector of absolute pixels
to a mixture of pixel/world and abs/rel.

"""
#
print "\t----\t convert Ex 1 \t----"
csys=cs.newcoordsys(direction=T, spectral=T)    # 3 axes
cout=csys.convert(coordin=[10,20,30],absin=[T,T,T],
unitsin=["pix","pix","pix"],
absout=[T,F,T], dopplerout=’optical’,
unitsout=["pix","arcsec","km/s"])
print cout
#[10.0, 1140.0058038878046, 1139.1354056919731]
#
"""

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