ADAS Subroutine d7grps

C
       subroutine d7grps(nwave, ndwave, wave, index) 
        
       
C-----------------------------------------------------------------------
C
C  ******************** FORTRAN77 FUNCTION: D7GRPS *********************
C
C  PURPOSE  : Puts wavelengths into a 5 bin histogram for automating
C             effective line selection in ADAS407. 
C
C  COMMENTS : Note that the number of bins is fixed and no attempt is 
C             made at clever adaptive methods of optimising case where
C             there is a large empty wavelength space between groups.
C
C  INPUT:  (I*4)   NWAVE   = number of wavelengths
C  INPUT:  (I*4)   NDWAVE  = max size of wavelength array
C  INPUT:  (R*8)   WAVE    = wavelengths
C
C  OUTPUT: (I*4)   INDEX   = indices (1->nbin) of wavelengths
C
C  ROUTINES:
C          ROUTINE    SOURCE    BRIEF DESCRIPTION
C          ------------------------------------------------------------
C          I4INDF     ADAS      Finds closet index in an array
C
C
C  AUTHOR   : Martin O'Mullane
C
C  VERSION  : 1.1                          
C  DATE     : 17-01-2002
C
C  MODIFIED : Martin O'Mullane  
C              - First version.
C
C-----------------------------------------------------------------------
      INTEGER             INDEX(NDWAVE),            NDWAVE,      NWAVE
      REAL*8              WAVE(NDWAVE)