vec2mean.f

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       subroutine vec2mean(vec,ge,aj2,xinit,xmean,ier)
 
c $header: /app/shared/rcs/irix-5.2/seawifsd/src/mops/mopsv4.1/swfnav/vec2mean.f,v 1.1 1995/01/17 23:03:07 seawifsd exp seawifsd $
c $log: vec2mean.f,v $
c revision 1.1  1995/01/17 23:03:07  seawifsd
c initial revision
c                                                                        
 
c  purpose:  this subroutine computes mean elements with respect to j2 
c   from an orbit vector.
c
c  calling arguments:
c
c  name         Type    i/o     description
c  --------     ----    ---     -----------
c  vec(6)       r*8      i      input orbit vector
c  ge           r*8      i      earth gravitational constant
c  aj2          r*8      i      j2 gravity term
c  xinit(6)     r*8      i      initial guess at mean elements
c  xmean(6)     r*8      o      output mean elements
c  ier          i*4      o      error flag(mean elements did not converge)
c
c
c  by: frederick s. patt, gsc, october 19, 1994
c
c  notes:  
c
c  modification history:
c
      implicit none
#include "nav_cnst.fin"
 
      real*8 vec(6),xinit(6),xmean(6),ge,aj2
      real*8 x(6),tmp(6),y(18)
      integer*4 i,ier
 
      call eqnox(vec,ge,y)
      x(1) = y(1)
      do i=2,6
          x(i) = y(i+5)
      end do
      tmp(1) = xinit(1)
      tmp(2) = xinit(2)
      do i=3,6
        tmp(i) = xinit(i)/radeg
      end do 
      tmp(6) = x(5) + x(6) - tmp(5)
      call kozsak2(3,ge,re,aj2,x,xmean,tmp,ier)
      do i=3,6
          xmean(i) = xmean(i)*radeg
      end do
      
      return
      end