replacing Matlab with python
I've been programming with Matlab for about 15 years, and with Python for about 10. It usually breaks down this way:
If you can satisfy the following conditions:
    1. You primarily use matrices and matrix operations
    2. You have the money for a Matlab license
    3. You work on a platform that mathworks supports
Then, by all means, use Matlab. Otherwise, if you have data structures other than matrices, want an open-source option that allows you to deliver solutions without worrying about licenses, and need to build on platforms that mathworks does not support; then, go with Python.
The matlab language is clunky, but the user interface is slick. The Python language is very nice -- with iterators, generators, and functional programming tools that matlab lacks; however, you will have to pick and choose to put together a nice slick interface if you don't like (or can't use) SAGE.
I hope that helps.
i am a engineering student and i have to do a lot of numerical processing, plots, simulations etc. The tool that i use currently is Matlab. I use it in my university computers for most of my assignments. However, i want to know what are the free options available. 
i have done some research and many have said that python is a worthy replacement for matlab in various scenarios. i want to know how to do all this with python. i am using a mac so how do i install the different python packages. what are those packages? is it really a viable alternative? what are the things i can and cannot do using this python setup?