Qalculate! is a multipurpose cross-platform desktop calculator.It is simple to use but provides power and versatility normally reserved for complicated math packages, as well as useful tools for everyday needs (such as currency conversion and percent calculation).Features include a large library of customizable functions, unit calculations and conversion, physical constants, symbolic calculations (including integrals and equations), arbitrary precision, uncertainty propagation, interval arithmetic, plotting, and a user-friendly interface (GTK, Qt and CLI).

It can be integrated into Kakoune as a drop-in replacement ofbc for a math prompt:

mapglobal normal =': prompt math: %{exec "a%val{text}<lt>esc>|qalc -t +u8 -f -<lt>ret>"}<ret>'

We can also define a command that will perform computations and display the results on the status bar like this:

define-command qalc -docstring"compute equation with Qalculate!" -params .. %{echo%sh{qalc${@}}}

Qalculate has many built-in functions and variables, we can improve theqalc command by generating autocomplete suggestions:

complete-command qalc shell-script-candidates %{    {echo $(qalc +u8 --list-functions | head -n -3);echo $(qalc +u8 --list-variables | head -n -3); } | tr'''\n' | sort -u}