Parameters

 Keyword  Posn  Type        Description
 -------  ----  ----        -----------
 INP       1    CHARACTER   Name of input dataset
 OUT       2    CHARACTER   Name of output data set
    -> GLOBAL.BINDS (the current binned dataset)
 DEGREE    3    INTEGER     Degree of required polynomial fit
 FIT       -    LOGICAL     FIT mode required?
    Hidden default = YES
 DTREND    -    LOGICAL     DTREND mode required?
    Hidden default = NO
 OVERWRITE -    LOGICAL     Overwrite input dataset?
    Hidden default = NO