subroutine comrho(wavlen,rhon)
c
c     subroutine comrho determins the 'rhon' (molecular depoarization factor) value for
c     for the given wavelength 'wavlen'.  A table of rhons and wavelengths  computed from
c     King's correction factor (see Bates...Planet. Space Sci. vol 32, 785-790, 1984)
c     are used for this purpose.  A linear interpolation method is used for determining 
c     rhon
c 
      implicit real*8 (a-h,o-z)    
      real*8 rnb(24)
      integer*4 la(24)
c
      data rnb/0.0454,0.0438,0.0422,0.0411,0.0400,0.0389,0.0378,0.0367,
     1         0.0356,0.0345,0.0339,0.0328,0.0323,0.0317,0.0317,0.0312,
     2         0.0306,0.0306,0.0301,0.0301,0.0301,0.0295,0.0295,0.0295/
c
      data la /2000,2050,2100,2150,2200,2250,2300,2400,2500,2600,2700,
     1         2800,2900,3000,3100,3200,3300,3400,3500,3600,3700,3800,
     2         3900,4000/
c
c
c     write(33,222)   wavlen
 222  format('comrho wavelength',1pe12.4)
      lam=int(wavlen+0.5)
      do i=1,24
         if(lam .gt. la(i) .and. lam .le. la(i+1)) then
              grad=(rnb(i+1)-rnb(i))/float(la(i+1)-la(i))
              rhon=rnb(i)+grad*(wavlen-float(la(i)))
         endif
      enddo
c
c     write(33,100) wavlen,rhon
100   format('wavelength rhon', 1p2e12.4)
c     return
      end