I've tried the following : 1)
sudo apt-get install python-nltk sudo apt-get install python-tk sudo apt-get install python-numpy sudo apt-get install python-matplotlib
The last 3 are just to avoid dependancy problems later.
2) I've also tried to build nltk from source.
None of the two approaches over work. This is the error I get:
Python 2.7.2 (default, Nov 1 2011, 23:57:57) [GCC 4.6.1] on linux3 Type "help", "copyright", "credits" or "license" for more information. >>> import nltk Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: No module named nltk