anchor.diff:  c******************************
   c
         do 100 jf=1,nf
  +c
            f0=fmin+df*dfloat(jf-1)
            p0=1.0d0/f0
   c
  
positive.code:  101     continue
  c
           do 102 i=1,n
              ph     = u(i)*f0
              ph     = ph-idint(ph)
              j      = 1 + idint(nb*ph)
              ibi(j) = ibi(j) + 1
              y(j) =   y(j) + v(i)
  
negative.code: c=================================
  c
        s=0.0d0
  c     t1 is the first elem in time array used as arbitrary epoch
        t1=t(1)
  c     these two loops below renormalize the magseries to 0.0
  c     by calculating the average of the magseries
  c     also rescales the times to the tprime = time - t1
        do 103 i=1,n
           u(i)=t(i)-t1
           s=s+x(i)
   103  continue
  c
        s=s/rn
  c
        do 109 i=1,n
           v(i)=x(i)-s
   109  continue
  