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Installing IPython and setup tools on Windows: A binary Windows installer for Python 2 or Python 3 is available on the IPython website. Also see http://ipython.org/ipython-doc/stable/install/install.html#windows.

Install setuptools with an installer from http://pypi.python.org/pypi/setuptools#files. Then install pip; for instance:

cd C:\Python27\scripts
python .\easy_install-27-script.py pip

Installing IPython On Mac OS X: Install the Apple Developer Tools (Xcode) if necessary. Xcode can be found on the OSX DVDs that came with your Mac or App Store. Follow the easy_install/pip instructions, or the installing from source instructions provided later in this section.

Installing IPython On Linux: Because there are so many Linux distributions, this section will not be exhaustive.

Installing IPython with easy_install or pip: Install IPython and all the dependencies required for the recipes in this chapter with easy_install, using the following command:

easy_install ipython pyzmq tornado readline

Alternatively, you can first install pip with easy_install, by typing the following command in your terminal:

easy_install pip

After that, install IPython using pip, with the following command:

sudo pip install ipython pyzmq tornado readline

Installing from source: If you want to use the bleeding edge development version, then installing from source is for you.

The pylab switch: The pylab switch automatically imports all the Scipy, NumPy, and Matplotlib packages. Without this switch, we would have to import these packages ourselves.

All we need to do is enter the following instruction on the command line:

$ ipython -pylab
Type "copyright", "credits" or "license" for more information.

IPython 0.12 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

Welcome to pylab, a matplotlib-based Python environment [backend: MacOSX].
For more information, type 'help(pylab)'.
In [1]: quit()
quit() or Ctrl 
+ D quits the IPython shell.

Saving a session: We might want to be able to go back to our experiments. In IPython, it is easy to save a session for later use, with the following command:

In [1]: %logstart
Activating auto-logging. Current session state plus future input saved.
Filename       : ipython_log.py
Mode           : rotate
Output logging : False
Raw input log  : False
Timestamping   : False
State          : active

Logging can be switched off as follows:

In [9]: %logoff
Switching logging OFF

Executing system shell commands: Execute system shell commands in the default IPython profile by prefixing the command with the ! symbol. For instance, the following input will get the current date:

In [1]: !date

In fact, any line prefixed with ! is sent to the system shell. Also, we can store the command output, as shown here:

In [2]: thedate = !date
In [3]: thedate

Displaying history: We can show the history of commands with the %hist command () for example:

In [1]: a = 2 + 2

In [2]: a
Out[2]: 4

In [3]: %hist
a = 2 + 2
a
%hist

This is a common feature in Command Line Interface (CLI) environments. We can also search through the history with the -g switch

In [5]: %hist -g a = 2
    1: a = 2 + 2

Calling the help function: Call the help command. Type a few characters of the function and press the Tab key:

Querying with a question mark: Another option is to put a question mark behind the function name. You will then, of course, need to know the function name, but you don't have to type help:

In [3]: arange?

Installing Matplotlib on Windows: Install with the Enthought distribution (http://www.enthought.com/products/epd.php).

It might be necessary to put the msvcp71.dll file in your C:\Windows\system32 directory. You can get it from http://www.dll-files.com/dllindex/dll-files.shtml?msvcp71.

Installing Matplotlib on Linux: Let's see how Matplotlib can be installed in the various distributions of Linux:

Installing from source: Download the latest source from the tar.gz release at Sourceforge (http://sourceforge.net/projects/matplotlib/files/) or from the Git repository using the following command:

git clone git://github.com/matplotlib/matplotlib.git

Once it has been downloaded, build and install as usual with the following command:

cd matplotlib
python setup.py install

Installing Matplotlib on Mac: Get the latest DMG file from http://sourceforge.net/projects/matplotlib/files/matplotlib/, and install it.

Running a notebook: We can start a notebook with the following code:

$ ipython notebook

[NotebookApp] Using existing profile dir: u'/Users/ivanidris/.ipython/profile_default'
[NotebookApp] The IPython Notebook is running at: http://127.0.0.1:8888
[NotebookApp] Use Control-C to stop this server and shut down all kernels.

As you can see, we are using the default profile. A server started on the local machine at port 8888. We will learn how to configure these settings later on in this chapter. The notebook is opened in your default browser; this is configurable as well:

IPython lists all the notebooks in the directory where you started the notebook. In this example no notebooks were found. The server can be stopped with Ctrl + C.

Running a notebook in the pylab mode: Run a web notebook in the pylab mode with the following command:

$ ipython notebook --pylab

This loads the Scipy, NumPy, and Matplotlib modules.

Running notebook with inline figures: We can display inline Matplotlib plots with the inline directive, using the following command:

$ ipython notebook --pylab inline

The Print option: The Print button doesn't actually print the notebook, but allows you to export the notebook as PDF or HTML document.

Downloading the notebook: Download your notebook to a location chosen by you, using the Download button. We can specify whether we want to download the notebook as .py file, which is just a normal Python program, or in the JSON format as a .ipynb file. The notebook we created in the previous recipe looks like the following, after exporting:

{
 "metadata": {
  "name": "Untitled1"
 }, 
 "nbformat": 2, 
 "worksheets": [
  {
    "cells": [
    {
      "cell_type": "code", 
      "collapsed": false, 
      "input": [
        "plot(sinc(a))"
      ], 
      "language": "python", 
      "outputs": [
      {
        "output_type": "pyout", 
        "prompt_number": 3, 
        "text": [
          "[<matplotlib.lines.Line2D at 0x103d9c690>]"
        ]
      }, 
      {
        "output_type": "display_data", 
        "png": "iVBORw0KGgoAAAANSUhEUgAAAXkAAAD9CAYAAABZVQdHAAAABHNCSVQICAgIf...
          mgkAAAAASUVORK5CYII=\n"
      }
      ], 
      "prompt_number": 3
    }
    ]
  }
  ]
}

Saving the notebook: Save the notebook using the Save button. This will automatically export a notebook in the native JSON .ipynb format. The file will be stored in the directory where you started IPython initially.