Array and macro resetting

Question

I would like to make an array with some automatic calculations. I use the package ftlpoint.

I made a test, but it does not work:

\newcommand{\line}[2]{%
    \fpMul{\produit}{#1}{#2}% Calculation
    \produit&%print result
    \produit&print result in another cell
}

On the first cell, no problem, but in the second cell, LaTeX says the command \produit doesn't exist (undefined control sequence).

How can do this?

Ps. Of course, my example is very simplified. I would like to make other calculations as well.

Answer 1

I think you need to make the definition of \produit global. Otherwise it goes out of existence when you move into another table cell.

\documentclass{article}
\usepackage{fltpoint}
\newcommand{\tline}[2]{%                                                        
    \fpMul{\temp}{#1}{#2}\global\edef\produit{\temp}% Calcul                    
    \produit&%seeing result                                                     
    \produit%seeing result on a other cell                                      
}
\begin{document}
\begin{tabular}{c|c}
\tline{2}{3}
\end{tabular}
\end{document}