Data analysis and Modifications

Functions take care about NaN's:  COVNAN, GRADNAN, SUMNAN
                                  MEDNAN, MEANNAN, STDNAN

Interpolation: AKIMA, INTERP0, INTERPG, INTERPC, INTERPM
               REPL_NAN, FILLNAN

Filtering: MEANIND1, MEANIND2, MFILTER, GRPMEAN, NOISE

Indexing: IND2GRP, GRP2IND, INSERT, REMFOLLW

Mapping: OBJMAP, OBANA, KRIGING

Griding: MONOGRID, MKGRID

other: INELLIP, ONLINE, PSPIKE, ZEROSIZE
       HEPIRO, JOINVEC, GET_EOF, ISOAREA