of Gell-Mann matrices
====================================

The Gell-Mann matrices, being the generators of the SU(3) group, are defined as follows: $$\begin{gathered}
\lambda^{1}=\left(
  \begin{array}{ccc}
    0 & 1 & 0 \\ [-2ex]
    1 & 0 & 0 \\ [-2ex]
    0 & 0 & 0 \\
  \end{array}
\right), \quad
\lambda^{2}=\left(
  \begin{array}{ccc}
    0 & -i & 0 \\[-2ex]
    i & 0 & 0 \\[-2ex]
    0 & 0 & 0 \\
  \end{array}
\right), \quad
\lambda^{3}=\left(
  \begin{array}{ccc}
    1 & 0 & 0 \\ [-2ex]
    0 & -1 & 0 \\ [-2ex]
    0 & 0 & 0 \\
  \end{array}
\right), \quad
\lambda^{4}=\left(
  \begin{array}{ccc}
    0 & 0 & 1 \\[-2ex]
    0 & 0 & 0 \\[-2ex]
    1 & 0 & 0 \\
  \end{array}
\right), \nonumber \\
\lambda^{5}=\left(
  \begin{array}{ccc}
    0 & 0 & -i \\ [-2ex]
    0 & 0 & 0 \\ [-2ex]
    i & 0 & 0 \\
  \end{array}
\right), \quad
\lambda^{6}=\left(
  \begin{array}{ccc}
    0 & 0 & 0 \\[-2ex]
    0 & 0 & 1 \\[-2ex]
    0 & 1 & 0 \\
  \end{array}
\right), \quad
\lambda^{7}=\left(
  \begin{array}{ccc}
    0 & 0 & 0 \\ [-2ex]
    0 & 0 & -i \\ [-2ex]
    0 & i & 0 \\
  \end{array}
\right), \quad
\lambda^{8}={1\over\sqrt{3}}\left(
  \begin{array}{ccc}
    0 & 0 & 1 \\[-2ex]
    0 & 0 