Subroutine: SORTDDI Purpose: SORTDDI sorts a Double precision array in Descending order and maintains the original order in an Index array. File: sort.c Author: K.G. Begeman Use: CALL SORTDDI( DATA, In/Output DOUBLE ARRAY INDX, In/Output INTEGER ARRAY NDAT ) Input INTEGER DATA Data array to sort. INDX Index array which maintains the same organization as the DATA array. NDAT Number of data points in DATA. Updates: Nov 4, 1989: KGB Document created.