FASTTIME (SEP93)               ftools.asca              FASTTIME (SEP93)



NAME
    fasttime - Corrects the time of SIS FAST mode data
    
    
USAGE
    fasttime infile outfile sourcey
    
    
DESCRIPTION
    This  task  takes  the  SIS  FAST  mode  data  and corrects the time
    written by FRFREAD to the correct time based on the Y value  of  the
    data.   The  output  can  either  be  directed  to  a  new  file, or
    optionally the input file's  time  may  be  overwritten.   The  time
    correction  is  based  on  the y position of the observed source, in
    raw pixels, which must be determined by the user.  This  is  usually
    done from BRIGHT mode data.
    
    
PARAMETERS
    
    infile [file name]
        The  name  of  the  input SIS FAST mode FITS file (and extension
        number in square brackets or separated by a +).
    
    outfile [file name]
        The name of the output FITS file.  If the outfile  parameter  is
        blank,  equal  to  '-'  or  the  same  as  the  input  file, the
        corrected times will be written to the input file.
    
    sourcey = 210 [integer]
        The Y pixel location of the source, as determined by  the  user.
        This is the RAW_Y value, usually found from BRIGHT mode data.
    
    (timecol = TIME) [string]
        The name of the TIME column.
    
    (ycolumn = RAWY) [string]
        The name of the Y column.
    
    (sensecase = yes) [boolean]
        Whether to be case sensitive about column names.
    
    
EXAMPLES
    1.  Correct the file fast.fits based on a source position of 210
    
         ft> fasttime fast.fits corrected.fits 210
    
    2.  As above, but put corrected values in the input file
    
         ft> fasttime fast.fits '-' 210
    
    
    
NOTES:
    Although  it  is  unlikely, correcting the time may result in a file
    with events out of time order.  It is very  important  to  sort  the
    events by time using FMEMSORT or FSORT if this is the case.
    
    Please   send  comments  and  recommendations  on  this  program  to 
    ascahelp@legacy.gsfc.nasa.gov
    
    
BUGS
    
    
SEE ALSO