# Altering the order of the variables in an equation system?

I'm wondering if it's possible to alter the order LaTeX outputs the equation.

The following code

\documentclass{article}
\usepackage{systeme}
\begin{document}
$\systeme{3+2t+s=x,s+2=y,1+t+2s=z}$
\end{document}


outputs

This really hurts my eyes as I would like the numbers to be displayed first, followed by the t and the s lastly.

• Welcome to TeX.SX! Please help us help you and add a minimal working example (MWE) that illustrates your problem. Reproducing the problem and finding out what the issue is will be much easier when we see compilable code, starting with \documentclass{...} and ending with \end{document}. – Stefan Pinnow Feb 21 at 13:19
• @StefanPinnow - I just converted the OP's code snippet into an MWE. :-) – Mico Feb 21 at 13:23
• @Mico Thank you, always, very much for your cordiality. – Sebastiano Feb 21 at 13:24
• According to the first full paragraph on page 2 of the package's user guide -- I'm translating loosely from the French original -- "the left-hand side material may contain constant terms. If that's the case, regardless of where on the left hand side the constant terms are entered, they will be displayed last, i.e., just before the equal signs." In short, your quest to have the numbers displayed first cannot be fulfilled, at least not by the current version of the package -- which is version 0.32, 13 Jan 2019, on my system. – Mico Feb 21 at 13:29
• If alternatives to systeme are considered, then see tex.stackexchange.com/questions/35174/… – Steven B. Segletes Feb 21 at 16:22

As I noted in an earlier comment, the systeme package doesn't currently allow you to start the left-hand-side material with a constant.

It's not too difficult, though, to achieve your formatting objective by employing an array environment.

\documentclass{article}
\usepackage{array} % for '\newcolumntype' macro
\newcolumntype{C}{>{{}}c<{{}}} % for columns with binary and relational operators
\newenvironment{myarray}[1]{%
\setlength\arraycolsep{0pt}
\left\{ \begin{array}{#1}}{%
\end{array} \right.}
\begin{document}
$\begin{myarray}{rCrCrCl} 3&+&2t&+& s&=&x\\ 2& & &+& s&=&y\\ 1&+& t&+&2s&=&z \end{myarray}$
\end{document}


Adding a [xxxx] to \systeme{3+2t+s=x,s+2=y,1+t+2s=z} sorted it out.
In this case \systeme[1ts]{3+2t+s=x,s+2=y,1+t+2s=z}.
• While this answer succeeds in placing 1 in first position in the third row, it does not place 3 and 2 in first position in rows 1 and 2, respectively. – Mico Feb 28 at 13:28