Last modified: 24 October 2023

DTF: Data Text Format

Multiple meanings of DTF

DTF can also refer to Dead Time Factor files.

The CIAo Data Model supports a variety of ASCII formats). One of these is the Data Text Format (DTF), which can be thought of as using the FITS concepts of header keywords and data blocks, but with ASCII rather than binary sections for the data.

The following dmcopy call creates a text file src.txt containing the contents of the (presumed FITS format) file src.pi.

unix% dmcopy src.pi "src.txt[opt kernel=text/dtf]"

This file can then be used with other CIAO tools - e.g.

unix% dmstat src.txt"[cols count_rate]"
    min:	0 	      @:	1
    max:	0.00094852952509 	      @:	71
   mean:	4.3287504051e-05
  sigma:	0.00010526767519
    sum:	0.044326404148
   good:	1024
   null:	0

or treated as an ASCII file:

unix% head src.txt
TFIELDS =                    4
TTYPE1  = "CHANNEL "           / PI
TFORM1  = "1J      "           / data format of field.
TUNIT1  = "channel "           / physical unit of field.
TLMIN1  =                    1
TLMAX1  =                 1024
unix% tail src.txt
MJDREF  =  5.0814000000000E+04 / MJD zero point for times
TSTART  =  7.9830949184000E+07 / Observation start time (MET)
TSTOP   =  7.9874795000000E+07 / Observation end time (MET)
TIMESYS = "TT      "           / Time system
TIMEUNIT= "s       "           / Time unit
CCD_ID  =                    0 / CCD for this table

7.9830989184000e+07 7.9867173869376e+07
7.9867177110326e+07 7.9874771584041e+07