kind of a bug
using SymPy
@vars α
[α α] # 1)
[α; α] # 2)
(α, α) # 3)
The weave2pdf would produce:
# 1) does not compile
\[\left[ \begin{array}{rr}α&α\end{array}\right]\]
# 2) does not compile
\[ \left[ \begin{array}{r}α\\α\end{array} \right] \]
# 3) compiles
\begin{lstlisting}
((*@\ensuremath{\alpha}@*), (*@\ensuremath{\alpha}@*))
\end{lstlisting}