<<< native
[ EArray
    [ AlignCenter ]
    [ [ [ EGrouped
            [ EIdentifier "x"
            , ESymbol Bin "-"
            , EFraction NormalFrac (EIdentifier "a") (EIdentifier "b")
            , EIdentifier "x"
            ]
        ]
      ]
    , [ [ EGrouped
            [ EIdentifier "x"
            , ESymbol Bin "-"
            , EFraction NormalFrac (ENumber "1") (EIdentifier "b")
            , EIdentifier "x"
            ]
        ]
      ]
    , [ [ EGrouped
            [ EIdentifier "x"
            , ESymbol Bin "-"
            , EFraction NormalFrac (ENumber "1") (ENumber "2")
            , EIdentifier "x"
            ]
        ]
      ]
    , [ [ EGrouped
            [ EIdentifier "x"
            , ESymbol Bin "-"
            , EFraction
                NormalFrac (ESuper (ENumber "1") (ENumber "2")) (EIdentifier "z")
            , EIdentifier "x"
            ]
        ]
      ]
    , [ [ EGrouped
            [ EIdentifier "x"
            , ESymbol Bin "-"
            , EFraction
                NormalFrac (EIdentifier "z") (ESuper (ENumber "1") (ENumber "2"))
            , EIdentifier "x"
            ]
        ]
      ]
    ]
]
>>> eqn
matrix{
ccol{ {x - a over b x} above {x - 1 over b x} above {x - 1 over 2 x} above {x - {1 sup 2} over z x} above {x - z over {1 sup 2} x} }
}