CellBasis

Evaluate basis functions in the cell.

Interface

܀ Interface

INTERFACE
  MODULE PURE FUNCTION CellBasis_Triangle(order, xij, refTriangle) RESULT(ans)
    INTEGER(I4B), INTENT(IN) :: order
    !! order of approximation inside the cell
    !! order should be greater than two
    REAL(DFP), INTENT(IN) :: xij(:, :)
    !! point of evaluation
    !! number of rows = nsd
    !! number of cols = number of points
    CHARACTER(*), INTENT(IN) :: refTriangle
    !! Reference triangle
    !! "BIUNIT"
    !! "UNIT"
    REAL(DFP) :: ans(SIZE(xij, 2), INT((order - 1) * (order - 2) / 2))
  END FUNCTION CellBasis_Triangle
END INTERFACE

️܀ See example

program main
  use easifembase
  use easifemClasses
  implicit none
  real(dfp), allocatable :: xij(:,:), avec(:)
  integer(i4b) :: ii, jj, cnt, n
  real(dfp), allocatable :: ans(:,:)
  integer(i4b) :: order
  type( VTKPlot_ ) :: aplot
  character(len=*), parameter :: fname="./results/"

  n = 51
  call reallocate(avec, n)
  call reallocate(xij, 2, int((n+1)*(n+2)/2))
  avec= linspace(0.0_DFP, 1.0_DFP, n)
  cnt=0
  do ii = 1, n
    do jj = 1, n-ii+1
      cnt=cnt+1
      xij(1,cnt) = avec(ii)
      xij(2,cnt) = avec(jj)
    end do
  end do

  order=5
  ans = CellBasis_Triangle(order=order, xij=xij, refTriangle="UNIT")
  do ii  = 1, size(ans,2)
    call aplot%scatter3D(x=xij(1,:), y=xij(2, :), z=ans(:,ii), &
      & filename=fname//"CellBasis( order=" // tostring(order) // &
        & " )" // tostring(ii) // &
        & ".vtp", &
      & label="P")
  end do
end program main

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