INTERP1D:EXAMPLE IN F90:
          ! Declare any routine as external to fill the place of m_slStateValue()
          external Extrap1D_LapseRate_X

          ! Declare the vertical levels (e.g. sigma values)
          real, dimension(srcNiNj, srcNk) :: levSrc  !(ni*nj, srcNk) points containing data
          real, dimension(dstNiNj, dstNk) :: levDst !(ni*nj, dstNk) points containing data

          ! Declare an array needed by the library
          integer, dimension(dstNiNj, dstNk) :: posn !(ni*nj, dstNk) points containing data

          ! Declare the state values and their derivatives (e.g. humidity)
          ! (The derivatives are used only by Interp1D_CubicWithDerivs.
          ! However, they must be declared even if a different Interp1D_* routine is used.)
          real, dimension(srcNiNj, srcNk) :: huSrc       !(ni*nj, srcNk) points containing data
          real, dimension(srcNiNj, srcNk) :: huDeriv  !(ni*nj, srcNk) points containing data
          real, dimension(dstNiNj, dstNk) :: huDst      !(ni*nj, dstNk) points containing data
          real, dimension(dstNiNj, dstNk) :: huDerivDst !(ni*nj, dstNk) points containing data

          ! Declare the variables that control extrapolation
          logical :: extrapEnableUp
          logical :: extrapEnableDown
          real :: extrapGuideUp
          real :: extrapGuideDown

          ! Declare the extension arrays
          integer :: numExtArraysIn, numExtArraysOut
          real, dimension(1, 1)  :: ExtArraysIn, ExtArraysOut

          ! Calculate and fill the array, posn
          call Interp1D_FindPos(ni*nj, srcNk, dstNk, &  ! elements used
                                srcNiNj, dstNiNj, & ! elements dimensioned

                                levSrc, &               ! source array
                                posn, levDst, &         ! destination arrays
                               )

          ! Fill in the input values
          levSrc=(/ ((i, i=1,srcNiNj), k=1,srcNk) /)
          levDst=(/ ((i+0.2, i=1,srcNiNj), k=1,srcNk) /)
          huSrc=40.4


          ! Perform the interpolation (any Interp1D_* routine may be
          ! chosen, except for Interp1D_FindPos), letting the algorithm
          ! extrapolate upward, but clamping downward extrapolation to
          ! the nearest-neighbour value
          extrapEnableUp = .true.
          extrapEnableDown = .false.
          extrapGuideUp = 0.         ! unused by this algorithm
          extrapGuideDown = 0.       ! unused by this algorithm
          numExtArraysIn = 0         ! unused by this algorithm
          numExtArraysOut = 0        ! unused by this algorithm
          call Interp1D_CubicLagrange_X(ni*nj, srcNk, dstNk, &             ! elements used
                                        srcNiNj, dstNiNj, &            ! elements dimensioned

                                        levSrc, huSrc, huDeriv, &          ! source arrays
                                        posn, levDst, huDst, huDerivDst, & ! destination arrays

                                        extrapEnableDown, extrapEnableUp, &
                                        extrapGuideDown, extrapGuideUp, &

                                        Extrap1D_LapseRate_X, &

                                        numExtArraysIn, numExtArraysOut, &
                                        ExtArraysIn, ExtArraysOut &
                                       )

          ! Overwrite the (upward) extrapolated values, based on a lapse rate (if desired)
          extrapGuideUp = -0.25      ! roll off to smaller values with higher levels

!         extrapGuideDown = +0.25    ! roll off to smaller values with lower levels 
                                     ! (if extrapGuideDown = .true.)

          call Extrap1D_LapseRate_X (ni*nj, srcNk, dstNk, &             ! elements used
                                     srcNiNj, dstNiNj, &            ! elements dimensioned

                                     levSrc, huSrc, huDeriv, &          ! source arrays
                                     posn, levDst, huDst, huDerivDst, & ! destination arrays

                                     extrapEnableDown, extrapEnableUp, &
                                     extrapGuideDown, extrapGuideUp, &

                                     Extrap1D_LapseRate_X, &

                                     numExtArraysIn, numExtArraysOut, &
                                     ExtArraysIn, ExtArraysOut &
                                    )




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Last updated: December 5, 2003