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$\rm \LaTeX$ Template for Simplex Tableaux

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Goal

To provide a good-looking template of simplex tableaux for users of Mathematics Stack Exchange.

\[ \begin{array}{crrrrrrr|l} & x_1 & x_2 & x_3 & x_4 & x_5 & x_6 & x_7 & \\ \hline x_4 & 0 & -3 & 7 & 1 & 0 & 0 & 2 & 2M -4 \\ x_5 & 0 & -9 & 0 & 0 & 1 & 0 & -1 & -M -3 \\ x_6 & 0 & 6 & -1 & 0 & 0 & 1 & -4^* & -4M +8 \\ x_1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & M \\ \hline & 0 & 1 & 1 & 0 & 0 & 0 & 2 & 2M \\ \text{ratio} & & & 1 & & & & 1/2 & \end{array} \]

Solution

A minimum working example 
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\begin{equation*}
  \begin{array}{crrrrrrr|l}
               & x_1 & x_2 & x_3 & x_4 & x_5 & x_6 &  x_7 &        \\ \hline
           x_4 &   0 &  -3 &   7 &   1 &   0 &   0 &    2 & 2M  -4 \\
           x_5 &   0 &  -9 &   0 &   0 &   1 &   0 &   -1 & -M  -3 \\
           x_6 &   0 &   6 &  -1 &   0 &   0 &   1 & -4^* & -4M +8 \\
           x_1 &   1 &   0 &   1 &   0 &   0 &   0 &    1 &      M \\ \hline
               &   0 &   1 &   1 &   0 &   0 &   0 &    2 &     2M \\
  \text{ratio} &     &     &   1 &     &     &     &  1/2 &
  \end{array}
\end{equation*}

More tableaux

(Added on DEC 13TH, 2016)

Two separated simplex tableaux created by the array environment aren’t vertically aligned. The visual effect isn’t good. As a result, I merged them to one big array.

\begin{equation*} \begin{array}{rrrrrrr|r} & x_1 & x_2 & x_3 & s_1 & s_2 & s_3 & \\ \hline s_1 & -2 & 0 & -2 & 1 & 0 & 0 & -60 \\ s_2 & -2 & -4^* & -5 & 0 & 1 & 0 & -70 \\ s_3 & 0 & -3 & -1 & 0 & 0 & 1 & -27 \\ \hline & 8 & 10 & 25 & 0 & 0 & 0 & 0 \\ \hline\hline s_1 & -2^* & 0 & -2 & 1 & 0 & 0 & -60 \\ x_2 & 1/2 & 1 & 5/4 & 0 & -1/4 & 0 & 35/2 \\ s_3 & 3/2 & 0 & 11/4 & 0 & -3/4 & 1 & 51/2 \\ \hline & 3 & 0 & 25/2 & 0 & 5/2 & 0 & -175 \\ \hline\hline x_1 & 1 & 0 & 1 & -1/2 & 0 & 0 & 30 \\ x_2 & 0 & 1 & 3/4 & 1/4 & -1/4 & 0 & 5/2 \\ s_3 & 0 & 0 & 5/4 & 3/4 & -3/4^* & 1 & -39/2 \\ \hline & 0 & 0 & 19/2 & 3/2 & 5/2 & 0 & -265 \\ \hline\hline x_1 & 1 & 0 & 1 & -1/2 & 0 & 0 & 30 \\ x_2 & 0 & 1 & 1/3 & 0 & 0 & -1/3 & 9 \\ s_2 & 0 & 0 & -5/3 & -1 & 1 & -4/3 & 26 \\ \hline & 0 & 0 & 41/3 & 4 & 0 & 10/3 & -330 \end{array} \end{equation*}
A sample simplex tableaulink
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\begin{equation*}
  \begin{array}{rrrrrrr|r}
      &  x_1 &  x_2 &  x_3 &  s_1 &    s_2 &  s_3 &       \\ \hline
  s_1 &   -2 &    0 &   -2 &    1 &      0 &    0 &   -60 \\
  s_2 &   -2 & -4^* &   -5 &    0 &      1 &    0 &   -70 \\
  s_3 &    0 &   -3 &   -1 &    0 &      0 &    1 &   -27 \\ \hline
      &    8 &   10 &   25 &    0 &      0 &    0 &     0 \\ \hline\hline
  s_1 & -2^* &    0 &   -2 &    1 &      0 &    0 &   -60 \\
  x_2 &  1/2 &    1 &  5/4 &    0 &   -1/4 &    0 &  35/2 \\
  s_3 &  3/2 &    0 & 11/4 &    0 &   -3/4 &    1 &  51/2 \\ \hline
      &    3 &    0 & 25/2 &    0 &    5/2 &    0 &  -175 \\ \hline\hline
  x_1 &    1 &    0 &    1 & -1/2 &      0 &    0 &    30 \\
  x_2 &    0 &    1 &  3/4 &  1/4 &   -1/4 &    0 &   5/2 \\
  s_3 &    0 &    0 &  5/4 &  3/4 & -3/4^* &    1 & -39/2 \\ \hline
      &    0 &    0 & 19/2 &  3/2 &    5/2 &    0 &  -265 \\ \hline\hline
  x_1 &    1 &    0 &    1 & -1/2 &      0 &    0 &    30 \\
  x_2 &    0 &    1 &  1/3 &    0 &      0 & -1/3 &     9 \\
  s_2 &    0 &    0 & -5/3 &   -1 &      1 & -4/3 &    26 \\ \hline
      &    0 &    0 & 41/3 &    4 &      0 & 10/3 &  -330
  \end{array}
\end{equation*}

Lessons learnt

In Mathematics Stack Exchange, never leave an empty line inside the array environment. Otherwise, the code won’t work.

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