Qalculate! is a multi-purpose desktop calculator for GNU/Linux. It is small and simple to use but with much power and versatility underneath. Features include customizable functions, units, arbitrary precision, plotting, and a user-friendly interface.
Version 0.5 includes a relatively large number of feature enhancements and fixes. The user interface has been partly redesigned (see screenshots) and does now have convenient completion for expressions. Note that gtk+-2.4 is recommended for this release, as it is needed for some of the new features.
* Redesigned GUI with menubar, history window, etc.
* Full completion of variables, functions and units in the expression entry
* Context-sensitive popup menu for the result
* Customizable expression entry font.
* A new solution for languages with comma as decimal point that actually should be working
* Actions for automatic unit conversion: convert to best unit and convert to base units
* Allow use of  for creation of matrices and vectors
* Polynomial division
* Imperial and U.S. capacity units
* New functions: sum (old sum renamed to total), product, area, code, char, cis, derangements, sec, re, im, time, week, weekday, year, month, day, asec, sech, asech, csc, acsc, csch, acsch, cot, acot, coth, acoth
* Use symbols for some common currencies in result and put them in front of the quantity, which is now fully supported in expressions
* Roman and sexagesimal numbers
* A new derivative function which does not depend on Giac
* Simple factorization without Giac
* A new convenient number class replaces fractions and integers internally
* Make use of the relations between e, pi and i to give exact results
* Define all trigonometric functions as expressions in relation to e and ln()
* Allow "today" for dates
* Fix ugly result display with gtk pixmap themes
* Fixes for newer Giac versions
* Some result display adjustments
* Fix some unit conversion cases
* Fix rem, mod and abs
* Fix trimmed, weighted and winsorized mean
* Fix date calculations with different basis
* Fix printing of exponent 1E...
* Some additional minor fixes