Common question. You cannot do column and matrix operations natively against S-Expressions (You need to parse the whole thing). This turns out to be very import

Common question. You cannot do column and matrix operations natively against S-Expressions (You need to parse the whole thing). This turns out to be very important and useful. S-Expressions need to be transversed in 1-D linear order. When you two-dimensionalize S-Expressions and remove the parens, you get Tree Notation.