A simple calculator made with python and some of its modules like tkinter, math and os.
You can save the current calculation at any time to the history with the Save Current Input button on the History Panel.
You can then click this function to insert it back to the line edit.
This history is saved to a file.
This calculator also supports variable insertion, and there are some formulas which can be inserted with the formula menu. The following example shows how it works.
{a} + {b} ? a=5 & b=3
turns to ...
5 + 3
evaluates to ...
8