ContinuumIO/blaze — pull request #252 by mrocklin (2014-05-02 12:33:26+00:00)
Title: Table 2

Refactor ColumnWise into `BinOp` and `UnaryOp`. Support standard arithmetic and mathy operations more smoothly. We leverage the fact that all projects use very similar names for their functions. E.g. everyone uses `+,-,*,/,**` and everyone uses `exp, cos, sin, ...`. We use these across `pandas: numpy`, `python: math`, `sqlalchemy: sqlalchemy.func`.

We also add an explicit `TableSymbol` to `TableExpr`. TableExprs now satisfy the following invariant

eval(str(expr)) == expr