rofi-calc

🖩 Do live calculations in rofi!

A rofi plugin that uses qalculate's qalc to parse natural language input and provide results.

Since this uses qalculate's amazing qalc you can try natural language queries such 500 + 25% or 5000 EUR to USD or 150 to hex. It can also solve linear equations on the fly. Try 60x + 30 = 50, for instance.

Run rofi like:

rofi -show calc -modi calc -no-show-match -no-sort

The result of the current input can be selected with Ctrl+Return, and history entries can be selected with Return. By default this will just output the equation/result.

The history file by default sits at $HOME/.local/share/rofi/rofi_calc_history in case you ever need to delete it or change it manually. You can disable persistent history if you don't like that.

Installation

Via package manager

From source

You need a C compilation toolchain (a cc, autoconf, pkg-config, ...), rofi (version >= 1.5) as well as qalculate (version > 2.0).

You will also need development headers for rofi. Depending on your distribution these may be included in different packages:

Arch Linux, Gentoo: included with rofi, libqalculate
OpenSUSE: zypper in rofi rofi-devel qalculate
Debian: apt install rofi-dev qalc libtool libtool-bin
Ubuntu: apt install rofi-dev qalc libtool
Solus: eopkg it rofi-devel libqalculate
CentOS: Install qalculate automake libtool (find rofi-devel headers yourself)
Fedora: dnf install qalculate automake libtool cairo-devel rofi-devel
VoidLinux: xbps-install -S rofi-devel libqalculate automake libtool
Others: look it up :)

Some distributions ship an extremely outdated version of qalculate so you might have to compile your own. If that is the case, see here.

rofi-calc uses autotools as build system. If installing from git, the following steps should install it:

$ git clone https://github.com/svenstaro/rofi-calc.git
$ cd rofi-calc/
$ mkdir m4
$ autoreconf -i
$ mkdir build
$ cd build/
$ ../configure
$ make
# make install

Advanced Usage

Use the -qalc-binary option to specify the name or location of qalculate's qalc binary. Defaults to qalc.
Use the -terse option to reduce the output of qalc to just the result of the input expression.
Use the -no-unicode option to disable qalc's Unicode mode.
Use the -calc-command option to specify a shell command to execute which will be interpolated with the following keys:
- {expression}: the left-side of the equation (currently not available when using -terse)
- {result}: the right of the equation
The following example copies the result to the clipboard upon pressing the key combination defined by -kb-accept-custom (by default Control+Return). NOTE: {result} should be quoted since it may contain characters that your shell would otherwise interpret:
```
  rofi -show calc -modi calc -no-show-match -no-sort -calc-command "echo -n '{result}' | xclip"
```
Alternatively, this example would immediately type out the result (using xdotool) wherever your cursor currently is (upon pressing Control+Return/-kb-accept-custom):
```
  rofi -modi calc -show calc -calc-command 'xdotool type --clearmodifiers "{result}"'
```
The -calc-command-history option will additionally add the output of qalc to history when the -calc-command is run. This will have no effect if -no-history is enabled.

It's convenient to bind it to a key combination in i3. For instance, you could use:

  bindsym $mod+c exec --no-startup-id "rofi -show calc -modi calc -no-show-match -no-sort > /dev/null"

To disable the bold font applied to the results by default, you can use the flag -no-bold and run rofi like:
```
  rofi -show calc -modi calc -no-show-match -no-sort -no-bold
```
To disable persistent history, use -no-persist-history:
```
  rofi -show calc -modi calc -no-show-match -no-sort -no-persist-history
```
This will disable writing and loading the history file and thus you'll lose and entered entries upon quitting rofi-calc.
To disable the history entirely, use -no-history:
```
  rofi -show calc -modi calc -no-show-match -no-sort -no-history -lines 0
```
The benefit of this is that you can simply enter a term and press Return and that'll already act on the result by printing it to stdout or via -calc-command if configured.
To automatically save last calculation to the history on rofi close, use -automatic-save-to-history.:
```
  rofi -show calc -modi calc -no-show-match -no-sort -automatic-save-to-history
```
This means that calculations are put into history even if you don't press Return.
To enable thousand separators in the output (e.g. 5 * 12 = 6,000, rather than 6000) add the following to ~/.config/qalculate/qalc.cfg
- For , separator:
```
  digit_grouping=2
```
- For space separator:
```
  digit_grouping=1
```
To use a different output format for numeric representations (for instance, some locales use , instead of . as a decimal separator), set LC_NUMERIC to a different value like this:
```
  LC_NUMERIC=de_DE.UTF-8 rofi -show calc -modi calc -no-show-match -no-sort
```
To set a different default locale, set your LC_MONETARY variable:
```
  LC_MONETARY=de_DE.UTF-8 rofi -show calc -modi calc -no-show-match -no-sort
```
Make sure the locale is actually available on your system!
Use the -hint-result option to specify the text of the hint before result.
Use the -hint-welcome option to specify the welcome text.

Custom Rofi Theme compatibility

If you are using a custom theme with rofi (e.g. rofi -show drun -theme ~/.config/rofi/mytheme.rasi) and don't see the result of the calculation, that's because the rofi-calc mode relies on the message widget that might be hidden by some themes.

In your mytheme.rasi file or any file, it might @import, look for the following

mainbox {
    children: [...]
}

make sure the list contains message
for example

mainbox {
    children: [inputbar, message, listview]
}

Reference Rofi docs: Layout, Base Widgets, Children

Development

If you're developing this, it might be helpful to start rofi directly with a locally compiled plugin like this:

autoreconf -i
mkdir build
cd build
../configure
make
rofi -plugin-path .libs -show calc -modi calc -no-show-match -no-sort