subroutine lmdif1(fcn,m,n,x,fvec,tol,info,iwa,wa,lwa)
      integer m,n,info,lwa
      integer iwa(n)
      real tol
      real x(n),fvec(m),wa(lwa)
      external fcn
c     **********
c
c     subroutine lmdif1
c
c     the purpose of lmdif1 is to minimize the sum of the squares of
c     m nonlinear functions in n variables by a modification of the
c     levenberg-marquardt algorithm. this is done by using the more
c     general least-squares solver lmdif. the user must provide a
c     subroutine which calculates the functions. the jacobian is
c     then calculated by a forward-difference approximation.
c
c     the subroutine statement is
c
c       subroutine lmdif1(fcn,m,n,x,fvec,tol,info,iwa,wa,lwa)
c
c     where
c
c       fcn is the name of the user-supplied subroutine which
c         calculates the functions. fcn must be declared
c         in an external statement in the user calling
c         program, and should be written as follows.
c
c         subroutine fcn(m,n,x,fvec,iflag
c         integer m,n,iflag
c         real x(n),fvec(m)
c         ----------
c         calculate the functions at x and
c         return this vector in fvec.
c         ----------
c         return
c         end
c
c         the value of iflag should not be changed by fcn unless
c         the user wants to terminate execution of lmdif1.
c         in this case set iflag to a negative integer.
c
c       m is a positive integer input variable set to the number
c         of functions.
c
c       n is a positive integer input variable set to the number
c         of variables. n must not exceed m.
c
c       x is an array of length n. on input x must contain
c         an initial estimate of the solution vector. on output x
c         contains the final estimate of the solution vector.
c
c       fvec is an output array of length m which contains
c         the functions evaluated at the output x.
c
c       tol is a nonnegative input variable. termination occurs
c         when the algorithm estimates either that the relative
c         error in the sum of squares is at most tol or that
c         the relative error between x and the solution is at
c         most tol.
c
c       info is an integer output variable. if the user has
c         terminated execution, info is set to the (negative)
c         value of iflag. see description of fcn. otherwise,
c         info is set as follows.
c
c         info = 0  improper input parameters.
c
c         info = 1  algorithm estimates that the relative error
c                   in the sum of squares is at most tol.
c
c         info = 2  algorithm estimates that the relative error
c                   between x and the solution is at most tol.
c
c         info = 3  conditions for info = 1 and info = 2 both hold.
c
c         info = 4  fvec is orthogonal to the columns of the
c                   jacobian to machine precision.
c
c         info = 5  number of calls to fcn has reached or
c                   exceeded 200*(n+1).
c
c         info = 6  tol is too small. no further reduction in
c                   the sum of squares is possible.
c
c         info = 7  tol is too small. no further improvement in
c                   the approximate solution x is possible.
c
c       iwa is an integer work array of length n.
c
c       wa is a work array of length lwa.
c
c       lwa is a positive integer input variable not less than
c         m*n+5*n+m.
c
c     subprograms called
c
c       user-supplied ...... fcn
c
c       minpack-supplied ... lmdif
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer maxfev,mode,mp5n,nfev,nprint
      real epsfcn,factor,ftol,gtol,xtol,zero
      data factor,zero /1.0e2,0.0e0/  
      info = 0
c
c     check the input parameters for errors.
c
      if (n .le. 0 .or. m .lt. n .or. tol .lt. zero
     *    .or. lwa .lt. m*n + 5*n + m) go to 10
c
c     call lmdif.
c
       
      maxfev = 200*(n + 1)
      ftol = tol
      xtol = tol
      gtol = zero
      epsfcn = zero
      mode = 1
      nprint = 0
      mp5n = m + 5*n
      call lmdif(fcn,m,n,x,fvec,ftol,xtol,gtol,maxfev,epsfcn,wa(1),
     *           mode,factor,nprint,info,nfev,wa(mp5n+1),m,iwa,
     *           wa(n+1),wa(2*n+1),wa(3*n+1),wa(4*n+1),wa(5*n+1))
      if (info .eq. 8) info = 4
   10 continue
      return
c
c     last card of subroutine lmdif1.
c
      end

      real function enorm(n,x)
      integer n
      real x(n)
c     **********
c
c     function enorm
c
c     given an n-vector x, this function calculates the
c     euclidean norm of x.
c
c     the euclidean norm is computed by accumulating the sum of
c     squares in three different sums. the sums of squares for the
c     small and large components are scaled so that no overflows
c     occur. non-destructive underflows are permitted. underflows
c     and overflows do not occur in the computation of the unscaled
c     sum of squares for the intermediate components.
c     the definitions of small, intermediate and large components
c     depend on two constants, rdwarf and rgiant. the main
c     restrictions on these constants are that rdwarf**2 not
c     underflow and rgiant**2 not overflow. the constants
c     given here are suitable for every known computer.
c
c     the function statement is
c
c       real function enorm(n,x)
c
c     where
c
c       n is a positive integer input variable.
c
c       x is an input array of length n.
c
c     subprograms called
c
c       fortran-supplied ... abs,sqrt
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer i
      real agiant,floatn,one,rdwarf,rgiant,s1,s2,s3,xabs,x1max,x3max,
     *     zero
      data one,zero,rdwarf,rgiant /1.0e0,0.0e0,3.834e-20,1.304e19/
      s1 = zero
      s2 = zero
      s3 = zero
      x1max = zero
      x3max = zero
      floatn = n
      agiant = rgiant/floatn
      do 90 i = 1, n
         xabs = abs(x(i))
         if (xabs .gt. rdwarf .and. xabs .lt. agiant) go to 70
            if (xabs .le. rdwarf) go to 30
c
c              sum for large components.
c
               if (xabs .le. x1max) go to 10
                  s1 = one + s1*(x1max/xabs)**2
                  x1max = xabs
                  go to 20
   10          continue
                  s1 = s1 + (xabs/x1max)**2
   20          continue
               go to 60
   30       continue
c
c              sum for small components.
c
               if (xabs .le. x3max) go to 40
                  s3 = one + s3*(x3max/xabs)**2
                  x3max = xabs
                  go to 50
   40          continue
                  if (xabs .ne. zero) s3 = s3 + (xabs/x3max)**2
   50          continue
   60       continue
            go to 80
   70    continue
c
c           sum for intermediate components.
c
            s2 = s2 + xabs**2
   80    continue
   90    continue
c
c     calculation of norm.
c
      if (s1 .eq. zero) go to 100
         enorm = x1max*sqrt(s1+(s2/x1max)/x1max)
         go to 130
  100 continue
         if (s2 .eq. zero) go to 110
            if (s2 .ge. x3max)
     *         enorm = sqrt(s2*(one+(x3max/s2)*(x3max*s3)))
            if (s2 .lt. x3max)
     *         enorm = sqrt(x3max*((s2/x3max)+(x3max*s3)))
            go to 120
  110    continue
            enorm = x3max*sqrt(s3)
  120    continue
  130 continue
      return
c
c     last card of function enorm.
c
      end

      subroutine fdjac2(fcn,m,n,x,fvec,fjac,ldfjac,iflag,epsfcn,wa)
      integer m,n,ldfjac,iflag
      real epsfcn
      real x(n),fvec(m),fjac(ldfjac,n),wa(m)
c     **********
c
c     subroutine fdjac2
c
c     this subroutine computes a forward-difference approximation
c     to the m by n jacobian matrix associated with a specified
c     problem of m functions in n variables.
c
c     the subroutine statement is
c
c       subroutine fdjac2(fcn,m,n,x,fvec,fjac,ldfjac,iflag,epsfcn,wa)
c
c     where
c
c       fcn is the name of the user-supplied subroutine which
c         calculates the functions. fcn must be declared
c         in an external statement in the user calling
c         program, and should be written as follows.
c
c         subroutine fcn(m,n,x,fvec,iflag)
c         integer m,n,iflag
c         real x(n),fvec(m)
c         ----------
c         calculate the functions at x and
c         return this vector in fvec.
c         ----------
c         return
c         end
c
c         the value of iflag should not be changed by fcn unless
c         the user wants to terminate execution of fdjac2.
c         in this case set iflag to a negative integer.
c
c       m is a positive integer input variable set to the number
c         of functions.
c
c       n is a positive integer input variable set to the number
c         of variables. n must not exceed m.
c
c       x is an input array of length n.
c
c       fvec is an input array of length m which must contain the
c         functions evaluated at x.
c
c       fjac is an output m by n array which contains the
c         approximation to the jacobian matrix evaluated at x.
c
c       ldfjac is a positive integer input variable not less than m
c         which specifies the leading dimension of the array fjac.
c
c       iflag is an integer variable which can be used to terminate
c         the execution of fdjac2. see description of fcn.
c
c       epsfcn is an input variable used in determining a suitable
c         step length for the forward-difference approximation. this
c         approximation assumes that the relative errors in the
c         functions are of the order of epsfcn. if epsfcn is less
c         than the machine precision, it is assumed that the relative
c         errors in the functions are of the order of the machine
c         precision.
c
c       wa is a work array of length m.
c
c     subprograms called
c
c       user-supplied ...... fcn
c
c       minpack-supplied ... spmpar
c
c       fortran-supplied ... abs,amax1,sqrt
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer i,j
      real eps,epsmch,h,temp,zero
      real spmpar
      data zero /0.0e0/
c
c     epsmch is the machine precision.
c
      epsmch = spmpar(1)
      write(*,*) "epsfcn,epsmch",epsfcn,epsmch
c      call exit
c
c      epsmch=1.18999999e-07
      eps = sqrt(amax1(epsfcn,epsmch))
      do 20 j = 1, n
         temp = x(j)
         h = eps*abs(temp)
c         write(*,*) h,eps,temp
c         call exit
         if (h .eq. zero) h = eps
         x(j) = temp + h
         call fcn(m,n,x,wa,iflag)
         if (iflag .lt. 0) go to 30
         x(j) = temp
         do 10 i = 1, m
            fjac(i,j) = (wa(i) - fvec(i))/h
c            if (j .eq. n) then
c            write(*,*) j,i,wa(i),fvec(i),h,fjac(i,j)
c            end if
   10       continue
c            call exit
c             write(*,*) fjac(:,1)
c             call exit
   20    continue
   30 continue
c      write(*,*) fjac(m-26,n)
c      call exit
      return
c
c     last card of subroutine fdjac2.
c
      end

      subroutine lmdif(fcn,m,n,x,fvec,ftol,xtol,gtol,maxfev,epsfcn,
     *                 diag,mode,factor,nprint,info,nfev,fjac,ldfjac,
     *                 ipvt,qtf,wa1,wa2,wa3,wa4)
      integer m,n,maxfev,mode,nprint,info,nfev,ldfjac
      integer ipvt(n)
      real ftol,xtol,gtol,epsfcn,factor,err(20)
      real x(n),fvec(m),diag(n),fjac(ldfjac,n),qtf(n),wa1(n),wa2(n),
     *     wa3(n),wa4(m)
      external fcn
c     **********
c
c     subroutine lmdif
c
c     the purpose of lmdif is to minimize the sum of the squares of
c     m nonlinear functions in n variables by a modification of
c     the levenberg-marquardt algorithm. the user must provide a
c     subroutine which calculates the functions. the jacobian is
c     then calculated by a forward-difference approximation.
c
c     the subroutine statement is
c
c       subroutine lmdif(fcn,m,n,x,fvec,ftol,xtol,gtol,maxfev,epsfcn,
c                        diag,mode,factor,nprint,info,nfev,fjac,
c                        ldfjac,ipvt,qtf,wa1,wa2,wa3,wa4)
c
c     where
c
c       fcn is the name of the user-supplied subroutine which
c         calculates the functions. fcn must be declared
c         in an external statement in the user calling
c         program, and should be written as follows.
c
c         subroutine fcn(m,n,x,fvec,iflag)
c         integer m,n,iflag
c         real x(n),fvec(m)
c         ----------
c         calculate the functions at x and
c         return this vector in fvec.
c         ----------
c         return
c         end
c
c         the value of iflag should not be changed by fcn unless
c         the user wants to terminate execution of lmdif.
c         in this case set iflag to a negative integer.
c
c       m is a positive integer input variable set to the number
c         of functions.
c
c       n is a positive integer input variable set to the number
c         of variables. n must not exceed m.
c
c       x is an array of length n. on input x must contain
c         an initial estimate of the solution vector. on output x
c         contains the final estimate of the solution vector.
c
c       fvec is an output array of length m which contains
c         the functions evaluated at the output x.
c
c       ftol is a nonnegative input variable. termination
c         occurs when both the actual and predicted relative
c         reductions in the sum of squares are at most ftol.
c         therefore, ftol measures the relative error desired
c         in the sum of squares.
c
c       xtol is a nonnegative input variable. termination
c         occurs when the relative error between two consecutive
c         iterates is at most xtol. therefore, xtol measures the
c         relative error desired in the approximate solution.
c
c       gtol is a nonnegative input variable. termination
c         occurs when the cosine of the angle between fvec and
c         any column of the jacobian is at most gtol in absolute
c         value. therefore, gtol measures the orthogonality
c         desired between the function vector and the columns
c         of the jacobian.
c
c       maxfev is a positive integer input variable. termination
c         occurs when the number of calls to fcn is at least
c         maxfev by the end of an iteration.
c
c       epsfcn is an input variable used in determining a suitable
c         step length for the forward-difference approximation. this
c         approximation assumes that the relative errors in the
c         functions are of the order of epsfcn. if epsfcn is less
c         than the machine precision, it is assumed that the relative
c         errors in the functions are of the order of the machine
c         precision.
c
c       diag is an array of length n. if mode = 1 (see
c         below), diag is internally set. if mode = 2, diag
c         must contain positive entries that serve as
c         multiplicative scale factors for the variables.
c
c       mode is an integer input variable. if mode = 1, the
c         variables will be scaled internally. if mode = 2,
c         the scaling is specified by the input diag. other
c         values of mode are equivalent to mode = 1.
c
c       factor is a positive input variable used in determining the
c         initial step bound. this bound is set to the product of
c         factor and the euclidean norm of diag*x if nonzero, or else
c         to factor itself. in most cases factor should lie in the
c         interval (.1,100.). 100. is a generally recommended value.
c
c       nprint is an integer input variable that enables controlled
c         printing of iterates if it is positive. in this case,
c         fcn is called with iflag = 0 at the beginning of the first
c         iteration and every nprint iterations thereafter and
c         immediately prior to return, with x and fvec available
c         for printing. if nprint is not positive, no special calls
c         of fcn with iflag = 0 are made.
c
c       info is an integer output variable. if the user has
c         terminated execution, info is set to the (negative)
c         value of iflag. see description of fcn. otherwise,
c         info is set as follows.
c
c         info = 0  improper input parameters.
c
c         info = 1  both actual and predicted relative reductions
c                   in the sum of squares are at most ftol.
c
c         info = 2  relative error between two consecutive iterates
c                   is at most xtol.
c
c         info = 3  conditions for info = 1 and info = 2 both hold.
c
c         info = 4  the cosine of the angle between fvec and any
c                   column of the jacobian is at most gtol in
c                   absolute value.
c
c         info = 5  number of calls to fcn has reached or
c                   exceeded maxfev.
c
c         info = 6  ftol is too small. no further reduction in
c                   the sum of squares is possible.
c
c         info = 7  xtol is too small. no further improvement in
c                   the approximate solution x is possible.
c
c         info = 8  gtol is too small. fvec is orthogonal to the
c                   columns of the jacobian to machine precision.
c
c       nfev is an integer output variable set to the number of
c         calls to fcn.
c
c       fjac is an output m by n array. the upper n by n submatrix
c         of fjac contains an upper triangular matrix r with
c         diagonal elements of nonincreasing magnitude such that
c
c                t     t           t
c               p *(jac *jac)*p = r *r,
c
c         where p is a permutation matrix and jac is the final
c         calculated jacobian. column j of p is column ipvt(j)
c         (see below) of the identity matrix. the lower trapezoidal
c         part of fjac contains information generated during
c         the computation of r.
c
c       ldfjac is a positive integer input variable not less than m
c         which specifies the leading dimension of the array fjac.
c
c       ipvt is an integer output array of length n. ipvt
c         defines a permutation matrix p such that jac*p = q*r,
c         where jac is the final calculated jacobian, q is
c         orthogonal (not stored), and r is upper triangular
c         with diagonal elements of nonincreasing magnitude.
c         column j of p is column ipvt(j) of the identity matrix.
c
c       qtf is an output array of length n which contains
c         the first n elements of the vector (q transpose)*fvec.
c
c       wa1, wa2, and wa3 are work arrays of length n.
c
c       wa4 is a work array of length m.
c
c     subprograms called
c
c       user-supplied ...... fcn
c
c       minpack-supplied ... spmpar,enorm,fdjac2,lmpar,qrfac
c
c       fortran-supplied ... abs,amax1,amin1,sqrt,mod
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer i,iflag,iter,j,l
      real actred,delta,dirder,epsmch,fnorm,fnorm1,gnorm,one,par,
     *     pnorm,prered,p1,p5,p25,p75,p0001,ratio,sum,temp,temp1,
     *     temp2,xnorm,zero
      real spmpar,enorm
C      common /errors/err
      data one,p1,p5,p25,p75,p0001,zero
     *     /1.0e0,1.0e-1,5.0e-1,2.5e-1,7.5e-1,1.0e-4,0.0e0/
c
c     epsmch is the machine precision.
c
      


      epsmch = spmpar(1)
c
      info = 0
      iflag = 0
      nfev = 0
      
c
c     check the input parameters for errors.
c
      if (n .le. 0 .or. m .lt. n .or. ldfjac .lt. m
     *    .or. ftol .lt. zero .or. xtol .lt. zero .or. gtol .lt. zero
     *    .or. maxfev .le. 0 .or. factor .le. zero) go to 300
      if (mode .ne. 2) go to 20
      do 10 j = 1, n
         if (diag(j) .le. zero) go to 300
   10    continue
   20 continue
c
c     evaluate the function at the starting point
c     and calculate its norm.
c
      iflag = 1
c      write(*,*) "before calling fcn"
c      write(*,*) "fvec_before: ",fvec(222)
c      write(*,*) "x_before: ",x
c      write(*,*) fjac(1,1)
c      call exit
      call fcn(m,n,x,fvec,iflag)
c      write(*,*) "x_after: ",x
c      write(*,*) "fvec(2): ",fvec(222)
c      write(*,*) fjac(1,1)
c      call exit
c      call exit
c      write(*,*) "fvec_after: ",fvec(1)
c      write(*,*) "after calling fcn"
c      call exit
      nfev = 1
      if (iflag .lt. 0) go to 300
      fnorm = enorm(m,fvec)
c
c     initialize levenberg-marquardt parameter and iteration counter.
c
      par = zero
      iter = 1
c
c     beginning of the outer loop.
c
   30 continue
c
c        calculate the jacobian matrix.
c      
c         write(*,*) "x",x
c         call exit
         iflag = 2
         write(*,*) fjac(1,1)
         call fdjac2(fcn,m,n,x,fvec,fjac,ldfjac,iflag,epsfcn,wa4)
         nfev = nfev + n
         write(*,*) "2",fjac(1,1)

c         write(*,*) wa4
c         call exit
c         write(*,*) "fvec(2): ",fvec(2)
c         call exit
         if (iflag .lt. 0) go to 300
c
c        if requested, call fcn to enable printing of iterates.
c
         if (nprint .le. 0) go to 40
         iflag = 0
         if (mod(iter-1,nprint) .eq. 0) call fcn(m,n,x,fvec,iflag)
         if (iflag .lt. 0) go to 300
   40    continue
c
c        compute the qr factorization of the jacobian.
c
c         write(*,*) fjac(1,1)
c	 call exit
         call qrfac(m,n,fjac,ldfjac,.true.,ipvt,n,wa1,wa2,wa3)
c         write(*,*) fjac(12,13)
c         write(*,*) "after qrfac"
c         call exit
         
c
c        on the first iteration and if mode is 1, scale according
c        to the norms of the columns of the initial jacobian.
c
         if (iter .ne. 1) go to 80
         if (mode .eq. 2) go to 60
         do 50 j = 1, n
            diag(j) = wa2(j)
            if (wa2(j) .eq. zero) diag(j) = one
   50       continue
   60    continue
c
c        on the first iteration, calculate the norm of the scaled x
c        and initialize the step bound delta.
c
         do 70 j = 1, n
            wa3(j) = diag(j)*x(j)
   70       continue
         xnorm = enorm(n,wa3)
         delta = factor*xnorm
         if (delta .eq. zero) delta = factor
   80    continue
c
c        form (q transpose)*fvec and store the first n components in
c        qtf.
c
c         write(*,*) fjac(12,13)
c         call exit
         do 90 i = 1, m
            wa4(i) = fvec(i)
   90       continue
c         write(*,*) wa4(222)
c         call exit
         do 130 j = 1, n
            if (fjac(j,j) .eq. zero) go to 120
            sum = zero
            do 100 i = j, m
c               write(*,*) fjac(i,j),wa4(i)
c               call exit               
               sum = sum + fjac(i,j)*wa4(i)
  100          continue
            temp = -sum/fjac(j,j)
c            write(*,*) sum
c            call exit
            do 110 i = j, m
               wa4(i) = wa4(i) + fjac(i,j)*temp
  110          continue
  120       continue
            fjac(j,j) = wa1(j)
            qtf(j) = wa4(j)
  130       continue
c            write(*,*) wa4(222)
c            call exit
c
c        compute the norm of the scaled gradient.
c
         gnorm = zero
         if (fnorm .eq. zero) go to 170
         do 160 j = 1, n
            l = ipvt(j)
            if (wa2(l) .eq. zero) go to 150
            sum = zero
            do 140 i = 1, j
               sum = sum + fjac(i,j)*(qtf(i)/fnorm)
  140          continue
            gnorm = amax1(gnorm,abs(sum/wa2(l)))
  150       continue
  160       continue
  170    continue
c
c        test for convergence of the gradient norm.
c
         if (gnorm .le. gtol) info = 4
         if (info .ne. 0) go to 300
c
c        rescale if necessary.
c
         if (mode .eq. 2) go to 190
         do 180 j = 1, n
            diag(j) = amax1(diag(j),wa2(j))
  180       continue
  190    continue
c
c        beginning of the inner loop.
c
  200    continue
c
c           determine the levenberg-marquardt parameter.
c
           
            write(*,*) "Starting lmpar"
            write(*,*) "x(2)",x(2),"wa4(222)",wa4(222)
            call lmpar(n,fjac,ldfjac,ipvt,diag,qtf,delta,par,wa1,wa2,
     *                 wa3,wa4)
c
c           store the direction p and x + p. calculate the norm of p.
c
            do 210 j = 1, n
               wa1(j) = -wa1(j)
               wa2(j) = x(j) + wa1(j)
               wa3(j) = diag(j)*wa1(j)
  210          continue
            pnorm = enorm(n,wa3)
c
c           on the first iteration, adjust the initial step bound.
c
            if (iter .eq. 1) delta = amin1(delta,pnorm)
c
c           evaluate the function at x + p and calculate its norm.
c
            iflag = 1
            write(*,*) "starting last-1 fcn"
            write(*,*) "wa4_before",wa4(222)
            call fcn(m,n,wa2,wa4,iflag)
            nfev = nfev + 1
c            call exit
            if (iflag .lt. 0) go to 300
            fnorm1 = enorm(m,wa4)
            write(*,*) "wa4",wa4(222)
c            call exit
c
c           compute the scaled actual reduction.
c
            write(*,*) "fnorm",fnorm,"fnorm1",fnorm1
            actred = -one
            if (p1*fnorm1 .lt. fnorm) actred = one - (fnorm1/fnorm)**2
c
c           compute the scaled predicted reduction and
c           the scaled directional derivative.
c
            do 230 j = 1, n
               wa3(j) = zero
               l = ipvt(j)
               temp = wa1(l)
               do 220 i = 1, j
                  wa3(i) = wa3(i) + fjac(i,j)*temp
  220             continue
  230          continue
            temp1 = enorm(n,wa3)/fnorm
            temp2 = (sqrt(par)*pnorm)/fnorm
            prered = temp1**2 + temp2**2/p5
            dirder = -(temp1**2 + temp2**2)
c
c           compute the ratio of the actual to the predicted
c           reduction.
c
            write(*,*) "ratio",ratio
            ratio = zero
            write(*,*) "ratio2",ratio
c            call exit
            if (prered .ne. zero) ratio = actred/prered
            write(*,*) "ratio3",ratio,actred,prered
c
c           update the step bound.
c
            if (ratio .gt. p25) go to 240
               if (actred .ge. zero) temp = p5
               if (actred .lt. zero)
     *            temp = p5*dirder/(dirder + p5*actred)
               if (p1*fnorm1 .ge. fnorm .or. temp .lt. p1) temp = p1
               delta = temp*amin1(delta,pnorm/p1)
               par = par/temp
               go to 260
  240       continue
               if (par .ne. zero .and. ratio .lt. p75) go to 250
               delta = pnorm/p5
               par = p5*par
  250          continue
  260       continue
c
c           test for successful iteration.
c
            if (ratio .lt. p0001) go to 290
c
c           successful iteration. update x, fvec, and their norms.
c
            do 270 j = 1, n
C               err(j)=abs(wa2(j)-x(j))
               x(j) = wa2(j)
               wa2(j) = diag(j)*x(j)
  270          continue
            do 280 i = 1, m
               fvec(i) = wa4(i)
  280          continue
            xnorm = enorm(n,wa2)
            fnorm = fnorm1
            iter = iter + 1
  290       continue
c
c           tests for convergence.
c
            if (abs(actred) .le. ftol .and. prered .le. ftol
     *          .and. p5*ratio .le. one) info = 1
            if (delta .le. xtol*xnorm) info = 2
            if (abs(actred) .le. ftol .and. prered .le. ftol
     *          .and. p5*ratio .le. one .and. info .eq. 2) info = 3
            write(*,*) "info",info
            if (info .ne. 0) go to 300
c
c           tests for termination and stringent tolerances.
c
            write(*,*) delta,epsmch,xnorm
            if (nfev .ge. maxfev) info = 5
            if (abs(actred) .le. epsmch .and. prered .le. epsmch
     *          .and. p5*ratio .le. one) info = 6
            if (delta .le. epsmch*xnorm) info = 7
            if (gnorm .le. epsmch) info = 8
            write(*,*) "info2",info
            if (info .ne. 0) go to 300
c
c           end of the inner loop. repeat if iteration unsuccessful.
c
            if (ratio .lt. p0001) go to 200
c
c        end of the outer loop.
c
         go to 30
  300 continue
c
c     termination, either normal or user imposed.
c
      write(*,*) "starting last fcn"
      if (iflag .lt. 0) info = iflag
      iflag = 0
      if (nprint .gt. 0) call fcn(m,n,x,fvec,iflag)
c      call exit
      return
c
c     last card of subroutine lmdif.
c
      end

      subroutine lmpar(n,r,ldr,ipvt,diag,qtb,delta,par,x,sdiag,wa1,
     *                 wa2)
      integer n,ldr
      integer ipvt(n)
      real delta,par
      real r(ldr,n),diag(n),qtb(n),x(n),sdiag(n),wa1(n),wa2(n)
c     **********
c
c     subroutine lmpar
c
c     given an m by n matrix a, an n by n nonsingular diagonal
c     matrix d, an m-vector b, and a positive number delta,
c     the problem is to determine a value for the parameter
c     par such that if x solves the system
c
c           a*x = b ,     sqrt(par)*d*x = 0 ,
c
c     in the least squares sense, and dxnorm is the euclidean
c     norm of d*x, then either par is zero and
c
c           (dxnorm-delta) .le. 0.1*delta ,
c
c     or par is positive and
c
c           abs(dxnorm-delta) .le. 0.1*delta .
c
c     this subroutine completes the solution of the problem
c     if it is provided with the necessary information from the
c     qr factorization, with column pivoting, of a. that is, if
c     a*p = q*r, where p is a permutation matrix, q has orthogonal
c     columns, and r is an upper triangular matrix with diagonal
c     elements of nonincreasing magnitude, then lmpar expects
c     the full upper triangle of r, the permutation matrix p,
c     and the first n components of (q transpose)*b. on output
c     lmpar also provides an upper triangular matrix s such that
c
c            t   t                   t
c           p *(a *a + par*d*d)*p = s *s .
c
c     s is employed within lmpar and may be of separate interest.
c
c     only a few iterations are generally needed for convergence
c     of the algorithm. if, however, the limit of 10 iterations
c     is reached, then the output par will contain the best
c     value obtained so far.
c
c     the subroutine statement is
c
c       subroutine lmpar(n,r,ldr,ipvt,diag,qtb,delta,par,x,sdiag,
c                        wa1,wa2)
c
c     where
c
c       n is a positive integer input variable set to the order of r.
c
c       r is an n by n array. on input the full upper triangle
c         must contain the full upper triangle of the matrix r.
c         on output the full upper triangle is unaltered, and the
c         strict lower triangle contains the strict upper triangle
c         (transposed) of the upper triangular matrix s.
c
c       ldr is a positive integer input variable not less than n
c         which specifies the leading dimension of the array r.
c
c       ipvt is an integer input array of length n which defines the
c         permutation matrix p such that a*p = q*r. column j of p
c         is column ipvt(j) of the identity matrix.
c
c       diag is an input array of length n which must contain the
c         diagonal elements of the matrix d.
c
c       qtb is an input array of length n which must contain the first
c         n elements of the vector (q transpose)*b.
c
c       delta is a positive input variable which specifies an upper
c         bound on the euclidean norm of d*x.
c
c       par is a nonnegative variable. on input par contains an
c         initial estimate of the levenberg-marquardt parameter.
c         on output par contains the final estimate.
c
c       x is an output array of length n which contains the least
c         squares solution of the system a*x = b, sqrt(par)*d*x = 0,
c         for the output par.
c
c       sdiag is an output array of length n which contains the
c         diagonal elements of the upper triangular matrix s.
c
c       wa1 and wa2 are work arrays of length n.
c
c     subprograms called
c
c       minpack-supplied ... spmpar,enorm,qrsolv
c
c       fortran-supplied ... abs,amax1,amin1,sqrt
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer i,iter,j,jm1,jp1,k,l,nsing
      real dxnorm,dwarf,fp,gnorm,parc,parl,paru,p1,p001,sum,temp,zero
      real spmpar,enorm
      data p1,p001,zero /1.0e-1,1.0e-3,0.0e0/
c
c     dwarf is the smallest positive magnitude.
c
      dwarf = spmpar(2)
c
c     compute and store in x the gauss-newton direction. if the
c     jacobian is rank-deficient, obtain a least squares solution.
c
      nsing = n
      do 10 j = 1, n
         wa1(j) = qtb(j)
         if (r(j,j) .eq. zero .and. nsing .eq. n) nsing = j - 1
         if (nsing .lt. n) wa1(j) = zero
   10    continue
      if (nsing .lt. 1) go to 50
      do 40 k = 1, nsing
         j = nsing - k + 1
         wa1(j) = wa1(j)/r(j,j)
         temp = wa1(j)
         jm1 = j - 1
         if (jm1 .lt. 1) go to 30
         do 20 i = 1, jm1
            wa1(i) = wa1(i) - r(i,j)*temp
   20       continue
   30    continue
   40    continue
   50 continue
      do 60 j = 1, n
         l = ipvt(j)
         x(l) = wa1(j)
   60    continue
c
c     initialize the iteration counter.
c     evaluate the function at the origin, and test
c     for acceptance of the gauss-newton direction.
c
      iter = 0
      do 70 j = 1, n
         wa2(j) = diag(j)*x(j)
   70    continue
      dxnorm = enorm(n,wa2)
      fp = dxnorm - delta
      if (fp .le. p1*delta) go to 220
c
c     if the jacobian is not rank deficient, the newton
c     step provides a lower bound, parl, for the zero of
c     the function. otherwise set this bound to zero.
c
      parl = zero
      if (nsing .lt. n) go to 120
      do 80 j = 1, n
         l = ipvt(j)
         wa1(j) = diag(l)*(wa2(l)/dxnorm)
   80    continue
      do 110 j = 1, n
         sum = zero
         jm1 = j - 1
         if (jm1 .lt. 1) go to 100
         do 90 i = 1, jm1
            sum = sum + r(i,j)*wa1(i)
   90       continue
  100    continue
         wa1(j) = (wa1(j) - sum)/r(j,j)
  110    continue
      temp = enorm(n,wa1)
      parl = ((fp/delta)/temp)/temp
  120 continue
c
c     calculate an upper bound, paru, for the zero of the function.
c
      do 140 j = 1, n
         sum = zero
         do 130 i = 1, j
            sum = sum + r(i,j)*qtb(i)
  130       continue
         l = ipvt(j)
         wa1(j) = sum/diag(l)
  140    continue
      gnorm = enorm(n,wa1)
      paru = gnorm/delta
      if (paru .eq. zero) paru = dwarf/amin1(delta,p1)
c
c     if the input par lies outside of the interval (parl,paru),
c     set par to the closer endpoint.
c
      par = amax1(par,parl)
      par = amin1(par,paru)
      if (par .eq. zero) par = gnorm/dxnorm
c
c     beginning of an iteration.
c
  150 continue
         iter = iter + 1
c
c        evaluate the function at the current value of par.
c
         if (par .eq. zero) par = amax1(dwarf,p001*paru)
         temp = sqrt(par)
         do 160 j = 1, n
            wa1(j) = temp*diag(j)
  160       continue
         call qrsolv(n,r,ldr,ipvt,wa1,qtb,x,sdiag,wa2)
         do 170 j = 1, n
            wa2(j) = diag(j)*x(j)
  170       continue
         dxnorm = enorm(n,wa2)
         temp = fp
         fp = dxnorm - delta
c
c        if the function is small enough, accept the current value
c        of par. also test for the exceptional cases where parl
c        is zero or the number of iterations has reached 10.
c
         if (abs(fp) .le. p1*delta
     *       .or. parl .eq. zero .and. fp .le. temp
     *            .and. temp .lt. zero .or. iter .eq. 10) go to 220
c
c        compute the newton correction.
c
         do 180 j = 1, n
            l = ipvt(j)
            wa1(j) = diag(l)*(wa2(l)/dxnorm)
  180       continue
         do 210 j = 1, n
            wa1(j) = wa1(j)/sdiag(j)
            temp = wa1(j)
            jp1 = j + 1
            if (n .lt. jp1) go to 200
            do 190 i = jp1, n
               wa1(i) = wa1(i) - r(i,j)*temp
  190          continue
  200       continue
  210       continue
         temp = enorm(n,wa1)
         parc = ((fp/delta)/temp)/temp
c
c        depending on the sign of the function, update parl or paru.
c
         if (fp .gt. zero) parl = amax1(parl,par)
         if (fp .lt. zero) paru = amin1(paru,par)
c
c        compute an improved estimate for par.
c
         par = amax1(parl,par+parc)
c
c        end of an iteration.
c
         go to 150
  220 continue
c
c     termination.
c
      if (iter .eq. 0) par = zero
      return
c
c     last card of subroutine lmpar.
c
      end

      subroutine qrfac(m,n,a,lda,pivot,ipvt,lipvt,rdiag,acnorm,wa)
      integer m,n,lda,lipvt
      integer ipvt(lipvt)
      logical pivot
      real a(lda,n),rdiag(n),acnorm(n),wa(n)
c     **********
c
c     subroutine qrfac
c
c     this subroutine uses householder transformations with column
c     pivoting (optional) to compute a qr factorization of the
c     m by n matrix a. that is, qrfac determines an orthogonal
c     matrix q, a permutation matrix p, and an upper trapezoidal
c     matrix r with diagonal elements of nonincreasing magnitude,
c     such that a*p = q*r. the householder transformation for
c     column k, k = 1,2,...,min(m,n), is of the form
c
c                           t
c           i - (1/u(k))*u*u
c
c     where u has zeros in the first k-1 positions. the form of
c     this transformation and the method of pivoting first
c     appeared in the corresponding linpack subroutine.
c
c     the subroutine statement is
c
c       subroutine qrfac(m,n,a,lda,pivot,ipvt,lipvt,rdiag,acnorm,wa)
c
c     where
c
c       m is a positive integer input variable set to the number
c         of rows of a.
c
c       n is a positive integer input variable set to the number
c         of columns of a.
c
c       a is an m by n array. on input a contains the matrix for
c         which the qr factorization is to be computed. on output
c         the strict upper trapezoidal part of a contains the strict
c         upper trapezoidal part of r, and the lower trapezoidal
c         part of a contains a factored form of q (the non-trivial
c         elements of the u vectors described above).
c
c       lda is a positive integer input variable not less than m
c         which specifies the leading dimension of the array a.
c
c       pivot is a logical input variable. if pivot is set true,
c         then column pivoting is enforced. if pivot is set false,
c         then no column pivoting is done.
c
c       ipvt is an integer output array of length lipvt. ipvt
c         defines the permutation matrix p such that a*p = q*r.
c         column j of p is column ipvt(j) of the identity matrix.
c         if pivot is false, ipvt is not referenced.
c
c       lipvt is a positive integer input variable. if pivot is false,
c         then lipvt may be as small as 1. if pivot is true, then
c         lipvt must be at least n.
c
c       rdiag is an output array of length n which contains the
c         diagonal elements of r.
c
c       acnorm is an output array of length n which contains the
c         norms of the corresponding columns of the input matrix a.
c         if this information is not needed, then acnorm can coincide
c         with rdiag.
c
c       wa is a work array of length n. if pivot is false, then wa
c         can coincide with rdiag.
c
c     subprograms called
c
c       minpack-supplied ... spmpar,enorm
c
c       fortran-supplied ... amax1,sqrt,min0
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer i,j,jp1,k,kmax,minmn
      real ajnorm,epsmch,one,p05,sum,temp,zero
      real spmpar,enorm
      data one,p05,zero /1.0e0,5.0e-2,0.0e0/
c
c     epsmch is the machine precision.
c
      epsmch = spmpar(1)
c      epsmch=1.18999999e-07
c
c     compute the initial column norms and initialize several arrays.
c
c      write(*,*) a(1,1)
c      a(1,1)=12.0003815
c      write(*,*) a(1,1)
c      write(*,*) enorm(m,a(1,1)),a(1,1)
c      call exit
      do 10 j = 1, n
c         write(*,*) m,a(1,j),enorm(m,a(1,j))
         acnorm(j) = enorm(m,a(1,j))
c         write(*,*) acnorm(j)
         rdiag(j) = acnorm(j)
c         write(*,*) "rdiag",rdiag(j)
         wa(j) = rdiag(j)
         if (pivot) ipvt(j) = j
   10    continue
c
c     reduce a to r with householder transformations.
c
c      call exit
      minmn = min0(m,n)
      do 110 j = 1, minmn
         if (.not.pivot) go to 40
c
c        bring the column of largest norm into the pivot position.
c
c	 if (j .eq. 9) then
c         write(*,*) "a(j,j)",a(j,j)
c           call exit
c         end if

         kmax = j
         do 20 k = j, n
c            write(*,*) k,kmax,rdiag(k),rdiag(kmax)
            if (rdiag(k) .gt. rdiag(kmax)) kmax = k
   20       continue
c         write(*,*) "kmax",kmax
c         if (j .eq. 12) then
c            kmax=88
c            call exit
c         end if
         if (kmax .eq. j) go to 40
         do 30 i = 1, m
c            write(*,*) a(i,j),a(i,kmax)
            temp = a(i,j)
            a(i,j) = a(i,kmax)
            a(i,kmax) = temp
   30       continue
c         write(*,*) "a(j,j)_2",a(j,j)
c         if (j .eq. 13) then
c           write(*,*) "a(j,j)_2",a(j,j)
c           call exit
c         end if


         rdiag(kmax) = rdiag(j)
         wa(kmax) = wa(j)
         k = ipvt(j)
         ipvt(j) = ipvt(kmax)
         ipvt(kmax) = k
   40    continue
c
c        compute the householder transformation to reduce the
c        j-th column of a to a multiple of the j-th unit vector.
c
         ajnorm = enorm(m-j+1,a(j,j))
c         write(*,*) "ajnorm",ajnorm,a(j,j)
         if (ajnorm .eq. zero) go to 100
         if (a(j,j) .lt. zero) ajnorm = -ajnorm
c         write(*,*) "ajnorm",ajnorm
         do 50 i = j, m
            a(i,j) = a(i,j)/ajnorm
c            if (j .eq. 13) then
c               write(*,*) "a(12,13)",a(12,13)
c               call exit
c            end if
   50       continue
         a(j,j) = a(j,j) + one
c         call exit
c
c        apply the transformation to the remaining columns
c        and update the norms.
c
         jp1 = j + 1
         if (n .lt. jp1) go to 100
         do 90 k = jp1, n
            sum = zero
            do 60 i = j, m
               sum = sum + a(i,j)*a(i,k)
   60          continue
            temp = sum/a(j,j)
            do 70 i = j, m
               a(i,k) = a(i,k) - temp*a(i,j)
   70          continue
            if (.not.pivot .or. rdiag(k) .eq. zero) go to 80
            temp = a(j,k)/rdiag(k)
            rdiag(k) = rdiag(k)*sqrt(amax1(zero,one-temp**2))
            if (p05*(rdiag(k)/wa(k))**2 .gt. epsmch) go to 80
            rdiag(k) = enorm(m-j,a(jp1,k))
            wa(k) = rdiag(k)
   80       continue
   90       continue
  100    continue
         rdiag(j) = -ajnorm
  110    continue

c      write(*,*) "a_3",a(12,13)
c      call exit
      return
c
c     last card of subroutine qrfac.
c
      end

      subroutine qrsolv(n,r,ldr,ipvt,diag,qtb,x,sdiag,wa)
      integer n,ldr
      integer ipvt(n)
      real r(ldr,n),diag(n),qtb(n),x(n),sdiag(n),wa(n)
c     **********
c
c     subroutine qrsolv
c
c     given an m by n matrix a, an n by n diagonal matrix d,
c     and an m-vector b, the problem is to determine an x which
c     solves the system
c
c           a*x = b ,     d*x = 0 ,
c
c     in the least squares sense.
c
c     this subroutine completes the solution of the problem
c     if it is provided with the necessary information from the
c     qr factorization, with column pivoting, of a. that is, if
c     a*p = q*r, where p is a permutation matrix, q has orthogonal
c     columns, and r is an upper triangular matrix with diagonal
c     elements of nonincreasing magnitude, then qrsolv expects
c     the full upper triangle of r, the permutation matrix p,
c     and the first n components of (q transpose)*b. the system
c     a*x = b, d*x = 0, is then equivalent to
c
c                  t       t
c           r*z = q *b ,  p *d*p*z = 0 ,
c
c     where x = p*z. if this system does not have full rank,
c     then a least squares solution is obtained. on output qrsolv
c     also provides an upper triangular matrix s such that
c
c            t   t               t
c           p *(a *a + d*d)*p = s *s .
c
c     s is computed within qrsolv and may be of separate interest.
c
c     the subroutine statement is
c
c       subroutine qrsolv(n,r,ldr,ipvt,diag,qtb,x,sdiag,wa)
c
c     where
c
c       n is a positive integer input variable set to the order of r.
c
c       r is an n by n array. on input the full upper triangle
c         must contain the full upper triangle of the matrix r.
c         on output the full upper triangle is unaltered, and the
c         strict lower triangle contains the strict upper triangle
c         (transposed) of the upper triangular matrix s.
c
c       ldr is a positive integer input variable not less than n
c         which specifies the leading dimension of the array r.
c
c       ipvt is an integer input array of length n which defines the
c         permutation matrix p such that a*p = q*r. column j of p
c         is column ipvt(j) of the identity matrix.
c
c       diag is an input array of length n which must contain the
c         diagonal elements of the matrix d.
c
c       qtb is an input array of length n which must contain the first
c         n elements of the vector (q transpose)*b.
c
c       x is an output array of length n which contains the least
c         squares solution of the system a*x = b, d*x = 0.
c
c       sdiag is an output array of length n which contains the
c         diagonal elements of the upper triangular matrix s.
c
c       wa is a work array of length n.
c
c     subprograms called
c
c       fortran-supplied ... abs,sqrt
c
c     argonne national laboratory. minpack project. march 1980.
c     burton s. garbow, kenneth e. hillstrom, jorge j. more
c
c     **********
      integer i,j,jp1,k,kp1,l,nsing
      real cos,cotan,p5,p25,qtbpj,sin,sum,tan,temp,zero
      data p5,p25,zero /5.0e-1,2.5e-1,0.0e0/
c
c     copy r and (q transpose)*b to preserve input and initialize s.
c     in particular, save the diagonal elements of r in x.
c
      do 20 j = 1, n
         do 10 i = j, n
            r(i,j) = r(j,i)
   10       continue
         x(j) = r(j,j)
         wa(j) = qtb(j)
   20    continue
c
c     eliminate the diagonal matrix d using a givens rotation.
c
      do 100 j = 1, n
c
c        prepare the row of d to be eliminated, locating the
c        diagonal element using p from the qr factorization.
c
         l = ipvt(j)
         if (diag(l) .eq. zero) go to 90
         do 30 k = j, n
            sdiag(k) = zero
   30       continue
         sdiag(j) = diag(l)
c
c        the transformations to eliminate the row of d
c        modify only a single element of (q transpose)*b
c        beyond the first n, which is initially zero.
c
         qtbpj = zero
         do 80 k = j, n
c
c           determine a givens rotation which eliminates the
c           appropriate element in the current row of d.
c
            if (sdiag(k) .eq. zero) go to 70
            if (abs(r(k,k)) .ge. abs(sdiag(k))) go to 40
               cotan = r(k,k)/sdiag(k)
               sin = p5/sqrt(p25+p25*cotan**2)
               cos = sin*cotan
               go to 50
   40       continue
               tan = sdiag(k)/r(k,k)
               cos = p5/sqrt(p25+p25*tan**2)
               sin = cos*tan
   50       continue
c
c           compute the modified diagonal element of r and
c           the modified element of ((q transpose)*b,0).
c
            r(k,k) = cos*r(k,k) + sin*sdiag(k)
            temp = cos*wa(k) + sin*qtbpj
            qtbpj = -sin*wa(k) + cos*qtbpj
            wa(k) = temp
c
c           accumulate the tranformation in the row of s.
c
            kp1 = k + 1
            if (n .lt. kp1) go to 70
            do 60 i = kp1, n
               temp = cos*r(i,k) + sin*sdiag(i)
               sdiag(i) = -sin*r(i,k) + cos*sdiag(i)
               r(i,k) = temp
   60          continue
   70       continue
   80       continue
   90    continue
c
c        store the diagonal element of s and restore
c        the corresponding diagonal element of r.
c
         sdiag(j) = r(j,j)
         r(j,j) = x(j)
  100    continue
c
c     solve the triangular system for z. if the system is
c     singular, then obtain a least squares solution.
c
      nsing = n
      do 110 j = 1, n
         if (sdiag(j) .eq. zero .and. nsing .eq. n) nsing = j - 1
         if (nsing .lt. n) wa(j) = zero
  110    continue
      if (nsing .lt. 1) go to 150
      do 140 k = 1, nsing
         j = nsing - k + 1
         sum = zero
         jp1 = j + 1
         if (nsing .lt. jp1) go to 130
         do 120 i = jp1, nsing
            sum = sum + r(i,j)*wa(i)
  120       continue
  130    continue
         wa(j) = (wa(j) - sum)/sdiag(j)
  140    continue
  150 continue
c
c     permute the components of z back to components of x.
c
      do 160 j = 1, n
         l = ipvt(j)
         x(l) = wa(j)
  160    continue
      return
c
c     last card of subroutine qrsolv.
c
      end

      real function spmpar(i)
      integer i,j
      if(i.eq.1) then
        j=4
      else if(i.eq.2) then
        j=1
      else if(i.eq.3) then
        j=2
      else
        stop
      end if

      spmpar=r1mach(j)
      
c      write(*,*) spmpar,j
c      call exit
      return
      end