db1val Subroutine

  1. mod_bspline.f90
  2. bspline
  3. db1val

public subroutine db1val(xval, idx, tx, nx, kx, bcoef, f, iflag, inbvx)

Arguments

Type IntentOptional AttributesName
real(kind=wp), intent(in) :: xval

x coordinate of evaluation point.
integer, intent(in) :: idx

x derivative of piecewise polynomial to evaluate.
real(kind=wp), intent(in), dimension(nx+kx):: tx

sequence of knots defining the piecewise polynomial in the x direction. (same as in last call to db1ink)
integer, intent(in) :: nx

the number of interpolation points in x. (same as in last call to db1ink)
integer, intent(in) :: kx

order of polynomial pieces in x. (same as in last call to db1ink)
real(kind=wp), intent(in), dimension(nx):: bcoef

the b-spline coefficients computed by db1ink.
real(kind=wp), intent(out) :: f

interpolated value
integer, intent(out) :: iflag

status flag: 0 : no errors, /=0 : error
integer, intent(inout) :: inbvx

initialization parameter which must be set to 1 the first time this routine is called, and must not be changed by the user.

Calls

proc~~db1val~~CallsGraph proc~db1val db1val proc~dbvalu dbvalu proc~db1val->proc~dbvalu proc~dintrv dintrv proc~dbvalu->proc~dintrv

Contents

Source Code

db1val

Source Code

    subroutine db1val(xval,idx,tx,nx,kx,bcoef,f,iflag,inbvx)

    implicit none

    integer,intent(in)                   :: idx      !! x derivative of piecewise polynomial to evaluate.
    integer,intent(in)                   :: nx       !! the number of interpolation points in x. (same as in last call to [[db1ink]])
    integer,intent(in)                   :: kx       !! order of polynomial pieces in x. (same as in last call to [[db1ink]])
    real(wp),intent(in)                  :: xval     !! x coordinate of evaluation point.
    real(wp),dimension(nx+kx),intent(in) :: tx       !! sequence of knots defining the piecewise polynomial in the x direction. (same as in last call to [[db1ink]])
    real(wp),dimension(nx),intent(in)    :: bcoef    !! the b-spline coefficients computed by [[db1ink]].
    real(wp),intent(out)                 :: f        !! interpolated value
    integer,intent(out)                  :: iflag    !! status flag: 0 : no errors, /=0 : error
    integer,intent(inout)                :: inbvx    !! initialization parameter which must be set to 1 the first time this routine is called, and must not be changed by the user.

    real(wp),dimension(3*kx) :: work

    f = 0.0_wp

    if (xval<tx(1) .or. xval>tx(nx+kx)) then
        write(error_unit,'(A)') 'db1val - x value out of bounds'
        iflag = 1
        return
    endif

    f = dbvalu(tx,bcoef,nx,kx,idx,xval,inbvx,work,iflag)

    endsubroutine db1val