c===================================================================c
c       analytic fitting formula for the numerical result II        c
c                                                                   c
c        J(r_s,R=0)=b(0)+b(1)*s+b(2)*s^2+ �c +b(10)*s^10            c
c          for  0.00001 <= r_s <= 0.1                               c
c                                                                   c
c===================================================================c
      program fitting_formulaeII
      
      implicit none

      real*8 rs,fitj,fitjr0

      write(6,*)'r_s=?   (0.00001< r_s <0.1)'
      read(5,*)rs

      fitj=fitjr0(rs)
      
      write(6,'(a6,f7.5,a6,f10.6)')'J(r_s=',rs,';R=0)=',fitj

      end

c ==== FITTING FORMULA OF J(rs;R=0) =========
      DOUBLE PRECISION FUNCTION fitjr0(rs)

      implicit none
      integer i
      real*8 rs,fj,c(0:10),s,rs0
      data c/ 0.450861E-01,0.113078E-02,0.312104E-02, 0.864302E-03,
     $        0.157214E-01,0.816962E-01,0.784921E-01,-0.680863E-01,
     $       -0.979967E-01,0.204907E-01,0.366713E-01/

c~~~~~~ ANALYTIC FITTING FORMULAE ~~~~~~~~~~
      rs0=0
      if(rs.lt.0.00001)then
         rs0=1-rs
         rs=0.00001
      endif
      s=(log10(rs)+3d0)/2d0
      fj=0
      if(s.ne.0)then
         do i=0,10
            fj=c(i)*s**i+fj
         enddo
      else
         fj=c(0)
      endif
      if(rs0.ne.0)then
         rs=1-rs0
      endif

      fitjr0=fj

      end