xy2rd: Translate a 2-D image pixel coordinate to right ascension

Package: imgtools

Usage

xy2rd infile[group] x y

Description

This task uses the group parameters CRVAL, CRPIX, and the CD matrix coefficients to translate a pixel coordinate to RA and DEC. Thus the epoch of RA and Dec is the same as these group parameters.

Parameters

infile [string]

Input image name. Images are calculated one at a time and wildcards are not supported. If no group number is specified, it assumes the default group of 1.

x [real]

X pixel coordinate.

y [real]

Y pixel coordinate.

(hms) = yes [boolean]

Print the output RA in hour-minute-second and DEC in degree-minute-second? If 'hms=no', output will be in decimal degrees.

(ra) [string]

The output right ascension.

(dec) [string]

The output declination.

Examples

1. Calculate RA and DEC of a pixel in the first group:

wf> xy2rd w1234567t.d0h 19 53

2. Calculate RA and DEC of a point in group 2, and produce output in decimal degrees:

wf> xy2rd w1234567t.d0h[2] 12.34 56.78 h-

Bugs

See also

rd2xy