### Versioning

The first time an IMB-FITS file is indexed, it is given a version number, starting at 1. Then, when it is calibrated, a new version of the entry is added in the index. For example, using the same example as before:

    MRTCAL> calibrate 1

    Calibrating   1.1 054-09   CONTROLD     30-SEP-2010  20:52:47.0 200 4MHZ  CALIBRATE   PSW NONE
    [calibration messages]

yields

    MRTCAL> mlist in
      N.V ProjId    Source         Date          UT     Scn Backe  ObsType    Swi Calibr
      1.1 054-09   CONTROLD     30-SEP-2010  20:52:47.0 200 4MHZ  CALIBRATE   PSW NONE
      1.2 054-09   CONTROLD     30-SEP-2010  20:52:47.0 200 4MHZ  CALIBRATE   PSW DONE E0HLI:254 E0VLI:198
      2.1 054-09   CONTROLD     30-SEP-2010  20:52:47.0 200 WILMA CALIBRATE   PSW NONE
      3.1 054-09   CONTROLD     30-SEP-2010  20:52:47.0 200 FTS   CALIBRATE   PSW NONE
      4.1 054-09   CONTROLD     30-SEP-2010  20:53:37.0 201 4MHZ  TRACKED     PSW NONE
      5.1 054-09   CONTROLD     30-SEP-2010  20:53:37.0 201 WILMA TRACKED     PSW NONE
      6.1 054-09   CONTROLD     30-SEP-2010  20:53:37.0 201 FTS   TRACKED     PSW NONE

One can see that a new entry, numbered 1.2, has been added to the input index. It is identical to the version 1.1, except that its calibration status is now DONE (and the calibration results are saved in the index file). The version 1.2 was inserted just after the version 1.1 so that the correct sorting is kept.

Beware that, when a new entry is added to the input index, the current index is NOT udpated. One has to call MFIND again. Note that MFIND finds only the latest versions of each entry:

    MRTCAL> mfind /backend 4mhz
    I-FIND,  2 entries in Current indeX
    MRTCAL> mlist
      N.V ProjId    Source         Date          UT     Scn Backe  ObsType    Swi Calibr
      1.2 054-09   CONTROLD     30-SEP-2010  20:52:47.0 200 4MHZ  CALIBRATE   PSW DONE E0HLI:254 E0VLI:198
      4.1 054-09   CONTROLD     30-SEP-2010  20:53:37.0 201 4MHZ  TRACKED     PSW NONE

Consider also that an entry can be calibrated several times, e.g. to test the effect of a modified calibration tuning. Each of these calibrations will increase the version number, producing a new entry in the index, memorizing its calibration results.