share/colnew/fortran/skale.f

   1       SUBROUTINE SKALE (N, MSTAR, KD, Z, XI, SCALE, DSCALE)
   2 C
   3 C**********************************************************************
   4 C
   5 C   purpose
   6 C            provide a proper scaling of the state variables, used
   7 C            to control the damping factor for a newton iteration [2].
   8 C
   9 C   variables
  10 C
  11 C            n      = number of mesh subintervals
  12 C            mstar  = number of unknomns in z(u(x))
  13 C            kd     = number of unknowns in dmz
  14 C            z      = the global unknown vector
  15 C            xi     = the current mesh
  16 C            scale  = scaling vector for z
  17 C            dscale = scaling vector for dmz
  18 C
  19 C**********************************************************************
  20 C
  21       IMPLICIT REAL*8 (A-H,O-Z)
  22       DIMENSION Z(MSTAR,1), SCALE(MSTAR,1), DSCALE(KD,1)
  23       DIMENSION XI(1), BASM(5)
  24 C
  25       COMMON /COLORD/ K, NCOMP, ID1, ID2, MMAX, M(20)
  26 C
  27       BASM(1) = 1.D0
  28       DO 50 J=1,N
  29         IZ = 1
  30         H = XI(J+1) - XI(J)
  31         DO 10 L = 1, MMAX
  32           BASM(L+1) = BASM(L) * H / DFLOAT(L)
  33   10    CONTINUE
  34         DO 40 ICOMP = 1, NCOMP
  35           SCAL = (DABS(Z(IZ,J)) + DABS(Z(IZ,J+1))) * .5D0 + 1.D0
  36           MJ = M(ICOMP)
  37           DO 20 L = 1, MJ
  38             SCALE(IZ,J) = BASM(L) / SCAL
  39             IZ = IZ + 1
  40   20      CONTINUE
  41           SCAL = BASM(MJ+1) / SCAL
  42           DO 30 IDMZ = ICOMP, KD, NCOMP
  43             DSCALE(IDMZ,J) = SCAL
  44   30      CONTINUE
  45   40    CONTINUE
  46   50  CONTINUE
  47       NP1 = N + 1
  48       DO 60 IZ = 1, MSTAR
  49         SCALE(IZ,NP1) = SCALE(IZ,N)
  50   60  CONTINUE
  51       RETURN
  52       END