demo1

This rmarkdown document mixes R and python programming, showing how an object created in R seems immutable when manipulated in python, but a copy made in python can be modified and returned to R with values created in python code.

Create R objects, retrieve in python

Here’s some R code:

x = c(1,2,3)
y = list(c(1,2), 3)

Now in python I prefix with r. to refer to my R values:

r.x

[1.0, 2.0, 3.0]

r.y

[[1.0, 2.0], 3.0]

r.x[1]

2.0

r.y[0]

[1.0, 2.0]

Can’t change passed object, but can modify copy

Change a value in python:

r.y[1] = 7
r.y

[[1.0, 2.0], 3.0]

z = r.y
z[1]

3.0

z[1] = 7.
r.zz = z

In R:

y

[[1]]
[1] 1 2

[[2]]
[1] 3

zz

[[1]]
[1] 1 2

[[2]]
[1] 7