The Descriptor Table

The list of pertinent MIDAS descriptors should be stored into a MIDAS table containing the following columns:

DESCR_INAME  (Character Column)          contains the list of MIDAS 
                                         descriptors to be mapped
                                         into the columns of the OST.

IPOS         (Integer Column)            contains for each descriptor
                                         the position of the element to be
                                         read. 

DESCR_ONAME  (Character Column)          contains for each descriptor the
                                         label of the column of the OST
                                         in which its values will be stored. 

OTYPE        (Character Column)          contains  for each descriptor the
                                         type of the column of the OST in
                                         which its values will be stored. 
                                         I (integer), R(eal), D(double 
                                         precision), C*n (character string)

The following columns will be automatically created in the OST:

1.

:FILENAME (containing the frame name)

2.

:MJD (containing the Modified Julian Date of the exposure).

If a descriptor contains more than one element, the one at the position defined in the column :IPOS is taken. The table may be created using the commands CREATE/TABLE, CREATE/COLUMN, and the different parameters may be entered using the Table Editor
(EDIT/TABLE). In the future we will supply on anonymous ftp templates for the different ESO instruments.

Table 15.2 shows a descriptor table created for NTT data obtained with the SUSI instrument. (Most of the examples in this document will be based on this set of 14 SUSI files.)

  

Table 15.2: A descriptor Table for SUSI exposures