<<< native
[ EDelimited
    "("
    ")"
    [ Right
        (EArray
           [ AlignCenter ]
           [ [ [ EIdentifier "U" ] ] , [ [ EIdentifier "V" ] ] ])
    ]
, ESymbol Rel "="
, EDelimited
    "("
    ")"
    [ Right
        (EArray
           [ AlignCenter ]
           [ [ [ EIdentifier "U" ] ] , [ [ EIdentifier "V" ] ] ])
    ]
]
>>> tex
\begin{pmatrix}
U \\
V
\end{pmatrix} = \begin{pmatrix}
U \\
V
\end{pmatrix}