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parkey tables



parkey -- Write an IRAF parameter to a header keyword.


parkey value output keyword


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.


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.


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 compname add+



This task was written by Bernie Simon.


keypar, keytab, partab, tabkey, tabpar

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