I want to use some Python libraries to replace MATLAB. How could I import Excel data in Python (for example using NumPy) to use them?

I don't know if Python is a credible alternative to MATLAB, but I want to try it. Is there a a tutorial? 

Answers: 

Depending on what kind of computations you are doing with MATLAB (and on which toolboxes you are using), Python could be a good alternative to MATLAB.

Python + NumPy + SciPy + Matplotlib are the right combination to start.

For the data, you can, for example, save your data directly in text file (assuming that you are not directly concerned by floating-point precision issues) and read it in Python.

If your data are Excel data, where each value is separated by a ";", you can for example read the file line by line, and use the split() method (with ";" as argument) to get each value.

For MATLAB up to version 7.1, it is possible to directly load .mat files from Python with the scipy.io.matlab.mio module.