Scientific Calculator Keyboard Challenge II

[Eddie W. Shore]

Link to my blog entry: http://edspi31415.blogspot.com/2016/02/s...board.html

Feeling creative? Ever dreamed of the perfect calculator? Here is a chance to design a calculator. It can cover any part of mathematics you want:

* Scientific
* Financial
* Programming/Graphing
* Algebraic and/or RPN (Reverse Polish Notation)

Or if you want to go a specialized route:

* Construction
* Unit Conversion
* Gaming
* Geometry Applications
* Civil Engineering
* Physics
* Astronomy
* Stock Market
* Common Every Day Applications

Rules:
* The keyboard must be used, including the arrow keys. Assume that the calculator will have the necessary screen size. You have 16 blank keys, of course, you can/should consider using shift and alpha keys.
* The keyboard has a double-wide Enter key. RPN and Hewlett Packard fans rejoice!
* The marked keys must remain.