Last modified: December 2013

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AHELP for CIAO 4.15


Context: Tools::Timing


Create Good Time Interval from Mission Time Line and limits


mtl_build_gti infile outfile mtlfile [userlimit] [lkupfile] [smooth]
[clobber] [verbose]


The mtl_build_gti tool creates a Good Time Interval from an input Mission Time Line file. The elements of the MTL that the GTI is created from is determined by a limits file, in a FITS file format, and an optional user provided limits string. An optional output MTL is created, which is the subset of columns of the input MTL that the GTI was determined from. As there is an option to perform smoothing on the data, the output MTL will be smoothed, if that option is selected. The input MTL will remain unchanged. An output GTI file will either be created, or if it is an already existent EVENT file, the GTI will be written to it. The GTI filtering syntax is explained in detail in the algorithms section. This format should be followed for both the contents of lkupfile, and the value of the userlimit parameter.





mtl_build_gti gti_mtl.fits out_gti.fits out_flt_mtl.fits smooth=yes


name type ftype def reqd
infile file input   yes
outfile file output   yes
mtlfile file output   yes
userlimit string input    
lkupfile file input    
smooth boolean   yes  
clobber boolean   no  
verbose integer   0  

Detailed Parameter Descriptions

Parameter=infile (file required filetype=input)

This is the input MTL files.

This is a FITS table with a BINTABLE first extension, which contains the MTL data. The file should contain the standard ASC header as well. The file's first column will be time.

Parameter=outfile (file required filetype=output)

Output GTI file

File to which the GTI will be written. An existing file may be specified, in which case the GTI information in that file is updated.

Parameter=mtlfile (file required filetype=output)

Output smoothed/filtered MTL file

This file is a copy of the input MTL file that may have had individual smoothing factors applied to the column data. The file will also be a subset of the input MTL, unless ALL the columns of the input MTL were filtered on in creating the GTI. In the case where all columns determine the GTI and no smoothing is applied, it will be a copy of the input. The purpose is to provide the user with the actual data that the GTI was created against. If this is set to NONE, none or "", the file won't be created.

Parameter=userlimit (string filetype=input)

Optional user defined limit string

This is a user input string that defines an (addtional) limit which the MTL data is checked against in creating the GTI.

Parameter=lkupfile (file filetype=input)

Lookup table defining which MTL columns to check against

This is the lookup table defining which MTL columns to check against. The data formats section describes what sort of limit conditions are allowable, the algorithm section how the limits are used. The file can also contain an optional keyword, GTICLASS, which determines the value of the HDUCLAS2 keyword to write to the output GTI file.

Parameter=smooth (boolean default=yes)

Smooth the input MTL data?

This smoothing is not done in place. The input is unchanged. The smoothing is done on a copy and written to the output. If this is set to no, all smoothing factors in the limits file are overriden and set to one.

Parameter=clobber (boolean default=no)

Clobber output file if it exists?

Parameter=verbose (integer default=0)

Debug level.

Debug levels range from 0 (nothing) to 5, which will describe in detail the processing that is occuring.


See dmgti

See Also

dmgti, dmimgcalc, dmmath, dmtcalc, mtl_build_gti