Those who have been following the discussion on http://planetkde.org/ will be aware of Roberto Alsina's ideas considering KCalc, and how it can be improved.
I thought he was on to something, so I made a C++ version, with a few extra features to make it useful.
Basically, this is a tool to let you type an expression (including trig, exponential, or logarithmic) functions and get an answer, including a history pane, support for Radians and Degrees, and a very compact mode.
Note on the recent RPN mode addition: abakus as of now doesn't have an persistent RPN mode value stack, so every expression you enter at this time has to result in exactly one value on the operand stack (e.g You can't do '2 +' after entering an expression, you need 'ans 2 +').
You can find a fuller description on the homepage, or by testing it out yourself!
You can make it really useful by using KControl to bind it to a key to make sure it's just a few keystrokes away!
10 years ago
This is a brief list of changes. For more info visit the homepage, or just try it out.
* Abakus supports the "," decimal separator correctly (both input and output).
* Show the most significant digits when an answer must be cut off due to space restrictions.
* Other minor stuff.
* DocBook documentation contributed by Jes Hall.
* A lot of the good user interface code was taken from SpeedCrunch by Ariya Hidayat. Abakus is now more pleasant to deal with.
* Added support for the GNU Multiple Precision library (in conjunction with MPFR). If you do not have it installed Abakus will fall back to its internal code.
* Improved error handling with the deriv() function.
* Fixed spelling of Ariya Hidayat's name.
* Added asinh(), acosh(), and atanh() functions.
* All functions that Abakus supports now have exact numerical derivatives. Abakus will still approximate for user-defined functions.
* Improvements to drag-and-drop, which is used slightly more evenly.
* You can use the F6 key to quickly select the expression editor.
* Fixed a crash bug when redefining a user-defined function that another user-defined function was using.
* Fixed a bug where the compact mode setting was incorrectly loaded.
* Fixed a bug with raising negative numbers to integral powers.
* Fixed a bug where the currently selected precision menu item could be deselected.
* Fixed a bug where some elements didn't have their precision updated when you selected a different precision.
* Fixed a bug where selecting Custom Precision would leave it checked even if you canceled the ensuing dialog.
* All hyperbolic trig functions consistently ignore the Degrees setting now, since it makes no sense when dealing with hyperbolic functions.