T-REX

T-REX - Terminal Rpn calculator EXperiment

This is a Reverse Polish Notation calculator similar to the traditional calculators from Hewlett Packard. See https://www.hpmuseum.org/rpn.htm for info on RPN.

Install by cloning this repo and putting astropanel.rb into your "bin" directory. Or you can simply run gem install astropanel.

This software runs in a terminal emulator and requires Ruby to be installed. It is tested only on Linux so far.

The stack is shown to the top left: L is the "Last X" register showing the previous value in X. T, Z, Y and X registers comprise the operating stack. Toggle US and European number formats by pressing '.

Functions available are shown under the stack registers. The orange symbol corresponds to the key to be pressed. For functions above each label (grey functions), press the Control key (Ctrl) and the orange key (asin = Ctrl+i).

For Rectangular to Polar conversions:

R-P: X value in x, Y in y - yields "θ" in y and "r" in x.
P-R: "θ" in y and "r" in x - yeilds X in x and Y in y.

Use the "f" key to set the fixed number of decimal places.

Use the "s" key to set the limit for viewing numbers in the "scientific" notation (e.g. 5e+06 for 5000000).

Content of registers #0-#9 are shown below the functions.

Store/recall using capital "S"/"R". "M" clears the regs.

You can undo all the way to the beginning of the session.

The 'H' key toggles the help text in the right pane.

The stack, register contents and modes are saved on Quit.

Alternative keys: Left/Right keys (in addition to "<") exchanges X and Y registers. Backspace clears the x register.

You can paste numbers directly to the x register the normal way (middle mouse button or Shift+Insert). You can copy/yank the number in the x register by pressing "y" to paste in into other applications (needs "xclip" installed).

To paste the full set of 10 memory registers to the clipboard, use "Y".

Additionally, for a world of possibilities, you can access the "Ruby mode" via '@'. Here you can address the stack directly, e.g. x = y + (z / t). Quit Ruby mode with Ctrl-C.