matplotlib: free plotting tool in Linux, (python code) similar Matlab

matplotlib

matplotlib is a pure Python 2D plotting library designed to bring publication quality plotting to Python with a syntax familiar to MATLAB users. All of the plotting commands in the pylab interface can be accessed either via a functional interface familiar to MATLAB users or an object oriented interface familiar to Python users.
The library uses numpy for handling large data sets and supports a variety of output backends including GTK GTKAgg, GTKCairo, FltkAgg, QtAgg, TkAgg and WXAgg.

 Features include:

• Generate:
• Plots
• Histograms
• Power spectra
• Bar charts
• Errorcharts
• Scatterplots and more
• Based on Python, a full-featured modern object-oriented programming language suitable for large-scale software development
• Suitable for fast scripting, including CGI scripts
• Free, open source, no license servers
• Native SVG support

Installation guide:

Install in ubuntu/debian:

- sudo apt-get build-dep python-matplotlib 

Install in Fedora/Red Hat:
- su -c "yum-builddep python-matplotlib"

- cd python folder
- python setup.py install

Source: http://matplotlib.org/

Error:
1) install matplotlib python version x.x required, which was not found in the registry.
  -->  Correction: You must install the python version which older or equal to the version of matplotlib.

2) ImportError: No module named matplotlib.pyplot

import six
ImportError: No module named 'six'
 --> Download and install this packages: https://pypi.python.org/pypi/six

ImportError: matplotlib requires dateutil
 --> Install: python-dateutil