The same think happens for python3-scipy. I installed python-numpy/scipy, python3-numpy/scipy/ using Synaptic. But they are installed under python3 not python3.2. My system is Ubuntu 12. Can anyone have experience of Synaptic?
ImportError: No module named numpy.
On Ubuntu 12.04 /usr/bin/python3.2 and /usr/bin/python3 is the same Python. Hence, if it is installed for /usr/bin/python3 it is also installed for /usr/bin/python3.2 (unless you have overwritten /usr/bin/python3.2, of course).
I therefore suspect that you have more than one installation of Python on your machine, perhaps a /usr/local/bin/python3.2?
When you install a module with Synaptic (or apt-get or aptitude etc) it will be installed only for the system-provided Python, ie the ones in /usr/bin. If you want to use it for any other installation, you have to install it for that installation as well, and then you need to follow the installation instructions from that packages documentation.
Often
pip install <packagename>will work, but not all packages are installable that way (most notably pip itself, of course).