--When I open the link of the parent, I see a graphical calculator, qalculate, but the description hints at something else, more of a text input calculator. The web app linked from qalculate looks like it. Is that available somewhere?--

Never mind.

I installed it, and it is two applications, one text input, one graphical, ... which also has text input, but responds differently from the examples. E.g. sqrt(72) doesn't mention it's 6√2. Confusing, but I'll find out, I guess.