I Wish I Had a Simple Calculator in My Bash

I’m sure you’ve found yourself needing to do quick calculations in the terminal. Sure, you could use a calculator app or a fancy spotlight bar, but sometimes the calculation is so simple that typing it directly would be easier. Wouldn’t it be nice if you could just type math "200 ** 2 / 200" and get your answer right away?

Context

Here’s a “real” example. Let’s say you’re checking some logs:

INFO combinations trained: 245
INFO documents written: 71

and you want to figure out roughly how many combinations each document has - in other words, you need to calculate 245 / 71.

Option B2

Probably the most general (and awesome) solution would be to write a super-duper Bash function that can be summoned at any time in your terminal, like a magical math genie:

Terminal window
# put this in your bashrc / zshrc
calcpy {
  python -c "from math import *; print($@)"
}

Run this in your terminal—because why not?

$ calcpy "245 / 71"
3.4507042253521125

Option C1

If you’re in Neovim (like 90% of the time), you can conjure a Vim command for this:

command! -nargs=+ Calc :execute '!python -c "from math import *; print(<args>)"'

Or use the Lua interface, because who doesn’t love a bit of Lua magic in their life? 🌙

vim.api.nvim_create_user_command('Calc', function(opts)
  vim.cmd('!python -c "from math import *; print(' .. opts.args .. ')"')
end, { nargs = '+' })

In both cases, you can summon your mathematical powers like this:

:Calc 245 / 71
3.4027777777777777