From the vantage point of a physicist and the kind of problems he would like a computer program to solve, what are the essential programming languages that a physicist should know.
I know C++ and I have worked in ROOT. I have also found Mathematica quiet essential, however since shifting to a linux machine I've been trying Sage which is also good, though not quiet at the same level right now. I have found C++ to be really fast, efficient, and best suited for stuff like Monte Carlo simulations. However, it appears that scimpy is also quiet popular. Would it be worthwhile to invest time in learning python, i.e would it have significant gains?
I also find the concept of functional programming languages much appealing. I think physicists unlike many programmers are more inclined to think this way rather than iteratively. Haskell sounds like a good candidate and I've also heard that it is ideal for simulating quantum algorithms on classical machines. Is anyone familiar with it?
Also what about scripting languages? I do not know any of those, except basic directory navigation in bash. Is there any utility in Perl and whatever is out there (I know little about these)