What is best practice for aligning distinct arrays or tables side-by-side?

Question

I have two related tables that could naturally be displayed side-by-side but don't have to be. However, it saves space to display them side-by-side rather than one atop the other. If I do so without tweaking the alignment, it looks ugly:

\begin{center}
    \(
        \begin{array}{l|cccccc}
            &   A   &   B   &   C   &   D   &   E   &   F   \\ \hline
        x^A &   1   &   3   &   1   &   1   &   1   &   2   \\
        x^B &   2   &   2   &   2   &   0   &   2   &   0   \\
        x^C &   3   &   1   &   3   &   1   &   0   &   1
        \end{array}
    \)
    \hspace{.5in}
    \(
        \begin{array}{l|cccc}
                    &   x           &   y       &   z   &   w   \\ \hline
            q=1     &   1           &   0       &   0   &   1   \\
            q\neq 1 &   0           &   1       &   1   &   1   \\
        \end{array}
    \)
\end{center}

Therefore, right now I am using the following hack to make the rows line up.

\begin{center}
    \(
        \begin{array}{l|cccccc}
            &   A   &   B   &   C   &   D   &   E   &   F   \\ \hline
        x^A &   1   &   3   &   1   &   1   &   1   &   2   \\
        x^B &   2   &   2   &   2   &   0   &   2   &   0   \\
        x^C &   3   &   1   &   3   &   1   &   0   &   1
        \end{array}
    \)
    \hspace{.5in}
    \(
        \begin{array}{l|cccc}
                    &   x           &   y       &   z   &   w   \\ \hline
            q=1     &   1           &   0       &   0   &   1   \\
            q\neq 1 &   0           &   1       &   1   &   1   \\
            \multicolumn{2}{c}{ }   &           &       &
        \end{array}
    \)
\end{center}

Is this bad practice? If so, what is the right way to do it?

If the answer is "two tables that need to be side-by-side are two tables that need to be one table"--and therefore that these two tables should not be side-by-side--so be it.

Answer 1

Since the contents is a display of math content, I'd suggest a display math environment with some fixed-width separation (like \qquad). Also align the arrays at the top:

\documentclass{article}
\begin{document}
I have two related tables that could naturally be displayed side-by-side but don't have to be. 
However, it saves space to display them side-by-side rather than one atop the other. If I do so 
without tweaking the alignment, it looks ugly:
\begin{center}
    \(
        \begin{array}{l|cccccc}
            &   A   &   B   &   C   &   D   &   E   &   F   \\ \hline
        x^A &   1   &   3   &   1   &   1   &   1   &   2   \\
        x^B &   2   &   2   &   2   &   0   &   2   &   0   \\
        x^C &   3   &   1   &   3   &   1   &   0   &   1
        \end{array}
    \)
    \hspace{.5in}
    \(
        \begin{array}{l|cccc}
                    &   x           &   y       &   z   &   w   \\ \hline
            q=1     &   1           &   0       &   0   &   1   \\
            q\neq 1 &   0           &   1       &   1   &   1   \\
        \end{array}
    \)
\end{center}
The following is a little cleaner:
\[
  \renewcommand{\arraystretch}{1.2}
  \begin{array}[t]{l|cccccc}
            &   A   &   B   &   C   &   D   &   E   &   F   \\ \hline
        x^A &   1   &   3   &   1   &   1   &   1   &   2   \\
        x^B &   2   &   2   &   2   &   0   &   2   &   0   \\
        x^C &   3   &   1   &   3   &   1   &   0   &   1
  \end{array}
  \qquad
  \begin{array}[t]{l|cccc}
                    &   x           &   y       &   z   &   w   \\ \hline
            q=1     &   1           &   0       &   0   &   1   \\
            q\neq 1 &   0           &   1       &   1   &   1
  \end{array}
\]
\end{document}​

This will ensure a consistent spacing with other display math content. Also, using a larger \arraystretch sometimes help with superscripts/subscripts running into other rows.