NAME

    gtltsumsun - Adds together livetime cubes produced by gtltcubesun.

USAGE

    gtltsumsun infile1 infile2 outfile

DESCRIPTION

    This tool facilitates multi-epoch analyses by summing the livetime
    contributions from each of two or more user specific input files
    and merges their GTI extensions. It checks to ensure that the
    input data sets are based on compatible HEALPix projection before
    they are summed. HEALPix is an acronym for Hierarchical Equal Area
    isoLatitude Pixelization (http://healpix.jpl.nasa.gov/). This is
    the only consistency check that is made between files. The input
    livetime cube files could be generated by gtltcubesun (see the
    gtltcubesun help).

PARAMETERS

    infile1 [filename]
    This is the name of the first livetime cube file or an ASCII file
    containing a list of livetime cube files, prepended with an "@"
    sign.  The livetime cube file could be generated by gtltcubesun (see
    the gtltcubesun help).

    infile2 [filename]
    This is the name of the second livetime cube file. It will be prompted
    for only if the first file is also a livetime cube file (i.e., not a
    list of files).

    (table = EXPOSURE) [string]
    Name of the extension containing the livetime.

    (table2 = WEIGHTED_EXPOSURE) [string]
    Name of extension containing livetime.

    outfile [filename]
    Output FITS file name.

    (chatter = 2) [integer]
    This parameter fixes the output verbosity: no screen output (0),
    nominal screen output (2), maximum verbosity (4).


    (clobber = yes) [boolean]
    If true, an existing file of the same name will be overwritten.

    (debug = no) [boolean]
    Activate debugging mode. This is a hidden parameter. The default
    value is "no". When debug is "no", all exceptions that are not
    caught and handled by individual tool-specific code are caught by
    a top-level exception handler that displays information about the
    exception and then exits. When debug is "yes", such exceptions are
    not caught by the top level code. Instead the tool produces a
    segmentation violation, which is more useful for debugging. When
    debugging mode is enabled, the tool produces more verbose output
    describing any errors or exceptions that are encountered.

    (gui = no) [boolean]
    Graphical user Interface (GUI) mode activated if "yes" is specified.

    (mode = ql) [string]
    Mode of automatic parameters: "h" for batch, "ql" for interactive.

EXAMPLES

    Parameters are passed following the FTOOLS model. They could be passed
    answering from a prompt, as a list in a command line, or by editing
    the parameter file.

    To be prompted for gtltsumsun simply type in the command line:

    > gtltsumsun

    You will be prompted for parameter values. Beware that not all
    parameters are prompted for; some of them are "hidden".  If you want to
    change one of the "hidden" parameters you should specify the value on
    the command line. For example if you do not want to overwrite an
    existing file you should type in the command line:

    > gtltsumsun clobber=no

    An example of how to run the tool is given below:

    > gtltsumsun
    Livetime cube 1 or list of files [] : expCubeSun_000001.fits
    Livetime cube 2 [none] : expCubeSun_000002.fits
    Output file [] : expCube.fits

    That last example could be also run on the command line as follows:

    >gtltsumsun infile1=expCubeSun_000001.fits infile2=expCubeSun_000002.fits \
     outfile= expCube.fits

SEE ALSO

     gtltcubesun

     gtexphpsun

     gtsuntemp