\subsection{Evaluate the torsion of a curve at given parameter values.}
\funclabel{s2553}
\begin{minipg1}
Evaluate the torsion of a curve at given parameter values
               ax[ 0 ],...,ax[ num\_ax - 1 ].
\end{minipg1} \\ \\
SYNOPSIS\\
        \> void s2553(\begin{minipg3}
             {\fov curve},  {\fov ax}, num\_ {\fov ax},  {\fov torsion}, jstat )
                \end{minipg3}\\
                \>\>    SISLCurve    \>  *{\fov curve};\\
                \>\>    double    \>  {\fov ax}[\,];\\
                \>\>    int    \>  {\fov num}\_ax;\\
                \>\>    double    \>  {\fov torsion}[\,];\\
                \>\>    int    \>  *{\fov jstat};\\
\\
ARGUMENTS\\
	\>Input Arguments:\\
        \>\>    {\fov curve}\> - \>  \begin{minipg2}
                     Pointer to the curve.
                               \end{minipg2}\\
        \>\>    {\fov ax}\> - \>  \begin{minipg2}
                     The parameter values
                               \end{minipg2}\\
        \>\>    {\fov num}\> - \>  \begin{minipg2}
                     No. of parameter values
                               \end{minipg2}\\
\\
	\>Output Arguments:\\
        \>\>    {\fov }\> - \>  \begin{minipg2}
             
                               \end{minipg2}\\
        \>\>    {\fov torsion}\> - \>  \begin{minipg2}
                     The "num\_ax" torsion values computed
                               \end{minipg2}\\
        \>\>    {\fov jstat} \> - \> Status messages\\
                \>\>\>\>\>           $> 0$ : Warning.\\
                \>\>\>\>\>           $= 0$ : Ok.\\
                \>\>\>\>\>           $< 0$ : Error.\\
\\
EXAMPLE OF USE\\
		\>      \{ \\

                \>\>    SISLCurve    \>  *{\fov curve};\\
                \>\>    double    \>  {\fov ax}[\,];\\
                \>\>    int    \>  {\fov num}\_ax;\\
                \>\>    double    \>  {\fov torsion}[\,];\\
                \>\>    int    \>  *{\fov jstat};\\                \>\>    \ldots \\
        \>\>s2553(\begin{minipg4}
             {\fov curve},  {\fov ax}, num\_ {\fov ax},  {\fov torsion}, jstat );
                \end{minipg4}\\
                \>\>    \ldots \\
		\>      \}
\end{tabbing}
