Subroutine spline_compute

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Subroutine `spline_compute_matrices`

$\begin{boxedminipage}{\textwidth} \begin{verbatim}call spline_compute_matrices(this,y2_matrix1,y2_matrix0)\end{verbatim} \end{boxedminipage}$

The y2 of the spline can also be computed using linear algebra. Following Numerical Recipes,

$\begin{displaymath} A Y'' = BY + C \end{displaymath}$

where

are matrices,

is a vector so

$\begin{displaymath} Y'' = A^{-1} B Y + A^{-1} C \end{displaymath}$

This subroutine computes these matrices, and stores them in spline%y2_matrix1 = inv(A)*B and spline%y2_matrix0 = inv(A)*C

this -- type(spline), intent(in)

y2_matrix1 -- real(dp), dimension(:,:), intent(out)

y2_matrix0 -- real(dp), dimension(:), intent(out)

spline_value function

gabor 2009-06-30