anchor.diff:      itplNode2BlockScal(:)=vrst(1,:)
     end function
     
  +  !> interpolate vector v within grid from node to facet
  +  function itplNode2FacetVect(v,grid)
  +    use moduleGrid
  +    use moduleBasicDataStruct
  +    double precision,intent(in)::v(:,:) !< node data to be interpolated
  +    type(typeGrid),intent(inout)::grid !< grid on which v is defined
  +    double precision,allocatable::itplNode2FacetVect(:,:) !< interpolated data on facet
  +    
  +    call reallocArr(itplNode2FacetVect,size(v,1),grid%nFacet)
  +    forall(i=1:grid%nFacet)
  +      itplNode2FacetVect(:,i)=sum(v(:,grid%Facet(i)%iNode(:)),2)/dble(grid%Facet(i)%nNode)
  +    end forall
  +  end function
  +  
  +  !> interpolate scaler v within grid from node to facet
  +  function itplNode2FacetScal(v,grid)
  +    use moduleGrid
  +    use moduleBasicDataStruct
  +    double precision,intent(in)::v(:) !< node data to be interpolated
  +    type(typeGrid),intent(inout)::grid !< grid on which v is defined
  +    double precision,allocatable::itplNode2FacetScal(:) !< interpolated data on facet
  +    double precision vv(1,size(v))
  +    double precision,allocatable::vrst(:,:)
  +    
  +    vv(1,:)=v(:)
  +    vrst=itplNode2FacetVect(vv,grid)
  +    call reallocArr(itplNode2FacetScal,size(vrst,2))
  +    itplNode2FacetScal(:)=vrst(1,:)
  +  end function
  +  
     !> interpolate vector v within grid from node to edge
     function itplNode2EdgeVect(v,grid)
       use moduleGrid
  
positive.code:     itplBlock2NodeScal(:)=vrst(1,:)
    end function
    
    !> interpolate matrix v within grid from block to interface using block center direction scheme
    function itplBCDMat(v,grid)
      use moduleGrid
  
negative.code:     module procedure::itplNode2BlockScal
    end interface
    public itplNode2Block
    
    !> interpolate from node to facet
    interface itplNode2Facet
      module procedure::itplNode2FacetVect
      module procedure::itplNode2FacetScal
    end interface
    public itplNode2Facet
    
    !> interpolate from node to edge
    interface itplNode2Edge
  