fets -- Coordinate transformation from Equatorial to Spacecraft.
This filter searches data tables for equatorial rows, i.e., those rows where FRAME = E. When an equatorial row is located, the RA, DEC, and associated covariances are transformed to direction cosines in the S frame using quaternion multiplication. (The transforming quaternion is computed from the telescope pointing RAV1, DECV1, and ROLLV3.) If an error occurs in retreiving position information, the star is skipped. An error in retreiving covariances will cause only the covariance transformation to be skipped.
After each column is read, its value is set to INDEF. If an error occurs anywhere in the transformation, that column will contain the character S, regardless of whether the transformation was completed, or was incomplete.
The following columns are used by fets:
INPUT OUTPUT ----- ------ RA X DEC Y RA_RA X,X DEC_DEC Y,Y RA_DEC X,Y FRAME FRAME Q1,Q2,Q3,Q4
1. Convert a data table from equatorial to spacecraft coordinates.
cl> fets intable
2. Convert a data table from equatorial to spacecraft coordinates, and create a new output table.
cl> fets intable new_table+ output_table="outtable"
3. Convert all tables having the suffix .tab.
cl> fets *.tab