SetUpCaseBlock Subroutine

    subroutine SetUpCaseBlock()
      !> Builds and writes block file.
      implicit none
      ! Work variables
      character(str64) :: filename
      real(wp)         :: L(3),xlo(3),xhi(3)
      integer          :: N(3), ngc, ilo(3),ihi(3), Nb(3)
      integer          :: dir
      integer          :: i,j,k
      real(wp)         :: r

      call parser%Get('Block file',  filename)
      call parser%Get("Domain size", L       )
      call parser%Get("Grid points", N       )
      call parser%Get("Ghost cells", ngc     )
      call parser%Get("Partition",   Nb      )

      ! Domain extents
      xlo = [-0.5_wp*L(1), 0.0_wp,-0.5_wp*L(3)]
      xhi = [ 0.5_wp*L(1), L(2),   0.5_wp*L(3)]
      ilo = [1,1,1] ; ihi = N

      ! Initialize the main block
      call block%Initialize(ngc,parallel)

      ! Setup the domain periodicity
      call block%SetPeriodicity([.true.,.false.,.true.])

      select case (CASE_ID)
      case (CASE_NORMAL_WALL, CASE_NORMAL_PAIR,CASE_NORMAL_IB)

        ! Create a uniform block
        call block%SetupUniformGrid(xlo,xhi,ilo,ihi)

      case (CASE_CHANNEL_WALL,CASE_CHANNEL_IB)

        ! Create a grid, locally refined at the wall
        ! ------------------------------------------
        call parser%Get("Stretching",  r  )

        associate (lo =>block%lo, hi=>block%hi)
          ! Setup bounds
          lo = [1,1,1]
          hi = N

          ! Initialize axes
          do dir=1,3
            call block%axis(dir)%Initialize(lo(dir),hi(dir),ngc)
          end do
          call block%SetConveniencePointers()
        end associate

        associate (x=>block%x, y=>block%y, z=>block%z, &
          lo =>block%lo, hi=>block%hi)
          ! Uniform x-axis
          do i=lo(1),hi(1)+1
            x(i)= (i-lo(1))*L(1)/real(hi(1)-lo(1)+1,wp)
          end do

          ! Stretched y-axis
          do j=lo(2),hi(2)+1
            y(j)= (j-lo(2))*L(2)/real(hi(2)-lo(2)+1,wp) - 0.5_wp*L(2)
            y(j)= 0.5_wp*L(2)*tanh(r*y(j)/(0.5_wp*L(2)))/tanh(r)
          end do

          ! Uniform z-axis
          do k=lo(3),hi(3)+1
            z(k)= (k-lo(3))*L(3)/real(hi(3)-lo(3)+1,wp) - 0.5_wp*L(3)
          end do
        end associate

      end select

      ! Partition block for parallel initializations
      call block%Partition(Nb)

      ! Write block to disk
      call block%Write(filename)

      return
    end subroutine SetUpCaseBlock