Comments

• If the parameter withsettings is set to false, the OAL is initialised by timeappend using an interm version of the output dataset, which is a copy of the input dataset plus the following dataset attributes:

  For EMOS1/2 and RGS:

  • CCDID 1
  • CCDNODE 0

  For EPN:

  • CCDID 0
  • QUADRANT 0
  • CCDNODE 0

  These attributes correspond to the default CCD and default node of the instrument in question. In the stage where TIME values are actually computed, timeappend sets the OAL state to the correct CCD explicitly, so the attributes CCDID and/or QUADRANT bear no affect on the eventual outcome of this task. The value of the attribute CCDNODE, on the other hand, does. The setting applied corresponds to the default PRIMARY node; if the user wishes to switch to the redundant node, then s/he should set the instrument properties explicitly via the withsettingsand associated parameters.

• See section  for efficiency considerations.