<<< native
[ EArray
    [ AlignCenter , AlignCenter , AlignCenter ]
    [ [ []
      , [ EText TextNormal "Stetching in base" ]
      , [ EText TextNormal "Stretching in script" ]
      ]
    , [ [ EText TextNormal "no mrows" ]
      , [ EOver
            False (ESymbol Accent "\8594") (EText TextNormal "maps to")
        ]
      , [ EOver
            False (EText TextNormal "maps to") (ESymbol Accent "\8594")
        ]
      ]
    , [ [ EText TextNormal "all in row" ]
      , [ EOver
            False (ESymbol Accent "\8594") (EText TextNormal "maps to")
        ]
      , [ EOver
            False (EText TextNormal "maps to") (ESymbol Accent "\8594")
        ]
      ]
    , [ [ EText TextNormal "op in row" ]
      , [ EOver
            False (ESymbol Accent "\8594") (EText TextNormal "maps to")
        ]
      , [ EOver
            False (EText TextNormal "maps to") (ESymbol Accent "\8594")
        ]
      ]
    , [ [ EText TextNormal "text in row" ]
      , [ EOver
            False (ESymbol Accent "\8594") (EText TextNormal "maps to")
        ]
      , [ EOver
            False (EText TextNormal "maps to") (ESymbol Accent "\8594")
        ]
      ]
    ]
]
>>> eqn
matrix{
ccol{ {""} above {roman "no mrows"} above {roman "all in row"} above {roman "op in row"} above {roman "text in row"} }
ccol{ {roman "Stetching in base"} above {-> to {roman "maps to"}} above {-> to {roman "maps to"}} above {-> to {roman "maps to"}} above {-> to {roman "maps to"}} }
ccol{ {roman "Stretching in script"} above {{roman "maps to"} to ->} above {{roman "maps to"} to ->} above {{roman "maps to"} to ->} above {{roman "maps to"} to ->} }
}