1.6 First steps with Python
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Working in the console
------------------------

It is always possible to use the Python console, to execute line-by-line instructions. To do it you need to open a MS-DOS (Windows) or terminal (Linux) window, write "python" and type Enter.
Then the Python console appears:

.. image:: console.jpeg

Creating scripts
------------------------

In practice you will not use the console for operations involving more than 2-3 lines of codes. Rather, you will use Python scripts.
Python scripts can be created with any text editor (e.g. Notepad).
For instance, you can create a file called "test.py". The ".py" extension is needed for the script to be able to run.
Just copy-paste the following lines in some text editor, and save the file:
::

	# -*- coding: utf-8 -*-
	print 2+2
	raw_input("Press Enter to close")

To execute the script, all you have to do is double-click on the file icon in the Explorer window or on the Desktop ! You should get the following window:

.. image:: Python.jpeg

Python scripts using AsPyLib
-----------------------------------------------

To use the whole AsPyLib package in a Python script, you need to add the following statement::

	import aspylib

If you only need one or two modules, then it's not needed to load the whole package and you can use::

	from aspylib import astro, calib

Then all functions are available in the form astro.function() or calib.function()

Resources
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There are plenty of tutorials and forums about Python on the web. These pages are especially interesting:

* `http://wiki.python.org/moin/BeginnersGuide/Programmers <http://wiki.python.org/moin/BeginnersGuide/Programmers>`_ 
* `http://www.scipy.org/Tentative_NumPy_Tutorial <http://www.scipy.org/Tentative_NumPy_Tutorial>`_ 
* `http://www.scipy.org/NumPy_for_Matlab_Users <http://www.scipy.org/NumPy_for_Matlab_Users>`_