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Tip 1235 Previous Tip • Next Tip

Created: May 20, 2006 Complexity: basic Author: Anon Minimum version: n/a Karma: 145/49 Imported from: Tip#1235

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Here is how to define and use a calculator, using embedded Python.

These two lines go in your vimrc:

:command! -nargs=+ Calc :py print <args>
:py from math import *

Now use it inside Vim:

:Calc 2**10+5,2**16,2**128
1029 65536 340282366920938463463374607431768211456
:Calc sin(pi/2), log(10)
1.0 2.302585

You have to have Vim compiled with Python support, and have python on your machine†. Use :version to see which features are included in your Vim.

If you don't have Python support in your Vim, but do have a python command, use this instead

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

You also get complex numbers and other goodies. Google for Python and math. Here is an example from complex math:

:py from cmath import *
:Calc exp(pi*1j) , " Euler famous identify e^i.pi = -1"
(-1+1.22460635382e-016j)

:Calc reduce(lambda a,b:a+b,range(1,100+1)), "Gauss' famous identity sum(1,100)"
5050

See references: http://docs.python.org/lib/module-cmath.html http://mathworld.wolfram.com/EulerFormula.html

[edit] dll

These days in Vim python support in windows is usually via a dll, installed separately from Vim; :version shows +python/dyn. Go to http://python.org/ to get the Python installer.