db1ink_multi Subroutine

private pure subroutine db1ink_multi(x, nx, fcn, kx, iknot, tx, bcoef, iflag)

Multiple-output version of db1ink: interpolates nf functions on the same grid, with the same knots. The last dimension of fcn and bcoef is the output index. Evaluate them with db1val (multiple-output version).

Arguments

Type IntentOptional Attributes Name
real(kind=wp), intent(in), dimension(:) :: x

(nx) array of abcissae. Must be strictly increasing.
integer(kind=ip), intent(in) :: nx

Number of abcissae
real(kind=wp), intent(in), dimension(:,:) :: fcn

(nx,nf) array of function values to interpolate: fcn(i1,j) is output j at grid point (x(i1))
integer(kind=ip), intent(in) :: kx

The order of spline pieces in

integer(kind=ip), intent(in) :: iknot

knot sequence flag (see db1ink_default)
real(kind=wp), intent(inout), dimension(:) :: tx

The (nx+kx) knots in the direction
real(kind=wp), intent(out), dimension(:,:) :: bcoef

(nx,nf) array of b-spline coefficients
integer(kind=ip), intent(out) :: iflag

status flag (see db1ink_default), or 6001 if fcn and bcoef do not have the same number of outputs (or it is zero)

Calls

proc~~db1ink_multi~~CallsGraph proc~db1ink_multi db1ink_multi proc~db1ink_default db1ink_default proc~db1ink_multi->proc~db1ink_default proc~check_inputs check_inputs proc~db1ink_default->proc~check_inputs proc~dbknot dbknot proc~db1ink_default->proc~dbknot proc~dbtpcf dbtpcf proc~db1ink_default->proc~dbtpcf proc~dbintk dbintk proc~dbtpcf->proc~dbintk proc~dbnslv dbnslv proc~dbtpcf->proc~dbnslv proc~dbintk->proc~dbnslv proc~dbnfac dbnfac proc~dbintk->proc~dbnfac proc~dbspvn dbspvn proc~dbintk->proc~dbspvn

Called by

proc~~db1ink_multi~~CalledByGraph proc~db1ink_multi db1ink_multi interface~db1ink db1ink interface~db1ink->proc~db1ink_multi proc~initialize_1d_auto_knots bspline_1d%initialize_1d_auto_knots proc~initialize_1d_auto_knots->interface~db1ink proc~initialize_1d_auto_knots_multi bspline_1d%initialize_1d_auto_knots_multi proc~initialize_1d_auto_knots_multi->interface~db1ink proc~initialize_1d_specify_knots bspline_1d%initialize_1d_specify_knots proc~initialize_1d_specify_knots->interface~db1ink proc~initialize_1d_specify_knots_multi bspline_1d%initialize_1d_specify_knots_multi proc~initialize_1d_specify_knots_multi->interface~db1ink proc~bspline_1d_constructor_auto_knots bspline_1d_constructor_auto_knots proc~bspline_1d_constructor_auto_knots->proc~initialize_1d_auto_knots proc~bspline_1d_constructor_specify_knots bspline_1d_constructor_specify_knots proc~bspline_1d_constructor_specify_knots->proc~initialize_1d_specify_knots interface~bspline_1d bspline_1d interface~bspline_1d->proc~bspline_1d_constructor_auto_knots interface~bspline_1d->proc~bspline_1d_constructor_specify_knots

Source Code

    pure subroutine db1ink_multi(x,nx,fcn,kx,iknot,tx,bcoef,iflag)

    implicit none

    integer(ip),intent(in)              :: nx     !! Number of \(x\) abcissae
    integer(ip),intent(in)              :: kx     !! The order of spline pieces in \(x\)
    real(wp),dimension(:),intent(in)    :: x      !! `(nx)` array of \(x\) abcissae. Must be strictly increasing.
    real(wp),dimension(:,:),intent(in) :: fcn  !! `(nx,nf)` array of function values to interpolate:
                                                   !! `fcn(i1,j)` is output `j` at grid point
                                                   !! (`x(i1)`)
    integer(ip),intent(in)              :: iknot  !! knot sequence flag (see [[db1ink_default]])
    real(wp),dimension(:),intent(inout) :: tx     !! The `(nx+kx)` knots in the \(x\) direction
    real(wp),dimension(:,:),intent(out) :: bcoef  !! `(nx,nf)` array of b-spline coefficients
    integer(ip),intent(out)             :: iflag  !! status flag (see [[db1ink_default]]),
                                                  !! or 6001 if `fcn` and `bcoef` do not have the
                                                  !! same number of outputs (or it is zero)

    integer(ip) :: nf  !! number of outputs
    integer(ip) :: j   !! output index

    nf = size(fcn,2,kind=ip)
    if (nf<1_ip .or. size(bcoef,2,kind=ip)/=nf) then
        iflag = 6001_ip
        return
    end if

    ! the knots are computed (if iknot=0) for the first output, and then reused
    do j = 1_ip, nf
        call db1ink_default(x,nx,fcn(:,j),kx,merge(iknot,1_ip,j==1_ip),&
                  tx,bcoef(:,j),iflag)
        if (iflag/=0_ip) return
    end do

    end subroutine db1ink_multi