anchor.diff:    ! ================================================================================================ !
     real(kind=fPrec) function polinterp(x,xvals,yvals,datalen,mpoints,jguess)
   
  +    use crcoall, only : lout
       use numerical_constants, only : zero
       implicit none
   
  
positive.code: 
    ! ================================================================================================ !
    !  A.Mereghetti, CERN, BE-ABP-HSS
    !  Last modified: 15-04-2019
    !  Given arrays xa and ya, each of length n, and given a value x, this function returns a
    !        value y, and an error estimate dy. If P(x) is the polynomial of degree N−1 such that
    !        P(xa_i)=ya_i, i=1,...,n , then the returned value y = P ( x ).
    !  This function implements Neville's method
    !  from Numerical Recipes in Fortran 77
    ! ================================================================================================ !
    real(kind=fPrec) function nevilleMethod(xa,ya,nn,x,dy)
      
  
negative.code:     integer,          intent(inout) :: jguess
      real(kind=fPrec), intent(in)    :: x, xvals(1:datalen), yvals(1:datalen)
  
      integer ii, jj, jMin, jMax
      real(kind=fPrec) dy
  
      polinterp = zero ! -Wmaybe-uninitialized
  