Run Python from R

First we set up the Python engine.

library(knitr)
library(runr)
py = proc_python(22222)
py$start()
knit_engines$set(python = function(options) {
    knitr:::wrap(py$exec(options$code), options)
})
opts_chunk$set(engine='python') 
# all the codes in the following chunks will be run in pyhton

import numpy as np
a = np.arange(5)

a # return nothing

print a # return values only if you print it

## [0 1 2 3 4]

def mean(x):
  return sum(x) / len(x)
print mean([1, 2, 3, 4, 5])

## 3

Do not forget to shut it down in the end.

py$stop()