parkey: Put an IRAF parameter into an image or table header keyword.

Package: nttools

Usage

parkey value output keyword

Description

This task changes the value of a header keyword in either a table or an image. If the value of the task parameter 'add' is "yes", the task will allow you to add a new keyword to the header, otherwise, adding a new keyword will cause an error. Type conversion is performed if the data type of the header keyword differs from the data type of the input parameter 'value'. If a new keyword is added to the file, the type is determined from the input value. The strings "yes", "y", "no", "n", "true", "t", "false", and "f", in either upper or lower case, are interpreted as boolean values.

Parameters

value [string]: Input value to be written to the header keyword. (Strings are case sensitive.)

output [file name]: Name of the file whose header keyword is to be changed.

keyword [string]: Name of the header keyword to be changed. (The name is not case sensitive.)

(add = no) [boolean]: Allow new header keywords to be added? If 'add = no', then existing keywords can take new values but no new keywords can be added to the file.

Examples

1. Set the header keyword 'OVERSCAN' in the file 'image.hhh' to 5:

tt> parkey 5 image.hhh overscan

2. Set the group parameter 'CTYPE1' in the second group of the same file to "ANGSTROM":

tt> parkey ANGSTROM image.hhh[2] ctype1

3. Set the header keyword 'YSTEP' to the value stored in the IRAF parameter 'x':

tt> parkey (x) image.hhh ystep

4. Add the keyword 'COMPNAME' to the table header and put the value "FILTER1" in it:

tt> parkey FILTER1 graph.tab compname add+

Bugs

References

This task was written by Bernie Simon.