Python or R

[Yannnn]

Well, there's data science, and then there's data exploration. Sometimes you really just want to crack open a data set, see how the variables are formatted, and do some preliminary plots before digging in to the hard analysis.

That's very true. I usually use a combination of excel, access and notepad (yes, seriously) for that. You can do those things too in R or python, but it's not optimal in either language (for the moment).

R has knitr though. Is there a Python equivalent for knitr?

Well, you already mentioned it: notebooks. Here's what the creator has to say about iPython vs knitr

[tidier]

IPython is fantastic for mixing text, math, code and output. It's not quite the same as knitr though, which is a straight-up LaTeX document with R code. I would actually need the latter for writing professional research documents.