Chandra X-Ray Observatory
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Last modified: December 2015

URL: http://cxc.harvard.edu/ciao/ahelp/add_key.html
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AHELP for CIAO 4.9

add_key

Context: crates

Synopsis

Add a keyword to a crate given a CrateKey object.

Syntax

add_key(crate, cratekey)

Description

Argument Description
crate A Crate object such as a TABLECrate or IMAGECrate
cratekey The CrateKey object storing the keyword and its value.

The add_key command adds the keyword to the end of the keyword list in the crate. If the keyword already exists, the value is replaced.

Only the crate is changed; the input file is unaffected. The write_file command can be used to save the modified crate to a file.

The set_key routine can be used to create a keyword without having to create a CrateKey object.

Example

>>> cr = read_file("evt2.fits")
>>> key = CrateKey()
>>> key.name = "TIMEDEL"
>>> key.value("0.00285")
>>> key.unit = "s"
>>> add_key(cr, key)

Create a new key named "TIMEDEL" with a value of 0.00285 and units of seconds, then add it to the crate.

Bugs

See the bug pages on the CIAO website for an up-to-date listing of known bugs.

Refer to the CIAO bug pages for an up-to-date listing of known issues.

See Also

contrib
make_image_crate, make_table_crate, scale_image_crate, smooth_image_crate, write_arrays, write_columns
crates
add_col, add_piximg, cratekey, delete_col, delete_key, delete_piximg, get_key, get_key_names, get_keyval, key_exists, read_file, read_pha, read_rmf, set_key, set_keyval, write_file, write_pha, write_rmf

Last modified: December 2015
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