[xCAS] requests

[parisse]

If you want to talk about Xcas, please register at the Xcas forum and post there.
For input, you can enter expressions in 2-d mode inside Xcas (select New expression in Expression menu) but I discourage this mode of entry (default is 1-d), because I think it's much easier to modify an existing input in 1-d mode (and it also requires much more ressources to implement an intuitive 2-d entry mode).