diff -r 88a01948450d -r d33698326409 saving_plots/script.rst
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+++ b/saving_plots/script.rst	Wed Dec 01 16:51:35 2010 +0530
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+.. Objectives
+.. ----------
+
+.. At the end of this tutorial, you will be able to 
+
+.. 1. Save plots using ``savefig()`` function.
+.. #. Save plots in different formats.
+
+
+.. Prerequisites
+.. -------------
+
+..   1. should have ``ipython`` and ``pylab`` installed. 
+..   #. getting started with ``ipython``.
+..   #. using plot command interactively.
+     
+.. Author              : Anoop Jacob Thomas <anoop@fossee.in>
+   Internal Reviewer   : Puneeth
+   External Reviewer   :
+   Language Reviewer   : Bhanukiran
+   Checklist OK?       : <10-11-2010, Anand, OK> [2010-10-05]
+
+.. #[Puneeth: Quickref missing.]
+
+=======
+Savefig
+=======
+
+{{{ Show the first slide }}}
+
+Hello and welcome to the tutorial saving plots.
+
+{{{ switch to next slide, outline slide }}}
+
+In this tutorial you will learn how to save plots using Python, saving
+in different formats, and locating the file in the file system.
+
+.. #[Puneeth: file-system is too technical.]
+
+{{{ switch to next slide, a sine wave}}}
+
+Start your IPython interpreter with the command ::
+
+  ipython -pylab
+
+As you know, it will start your IPython interpreter with the required
+python modules for plotting and saving your plots.
+
+{{{ Open ipython }}}
+
+Now let us plot something, let us plot a sine wave from minus 3 pi to
+3 pi. Let us start by calculating the required points for the plot. It
+can be done using linspace as, ::
+
+  x = linspace(-3*pi,3*pi,100)
+
+We have stored required points in x. Now let us plot the points using
+the statement ::
+
+  plot(x,sin(x))
+
+{{{ Keep the plot open }}}
+
+Done! we have made a very basic sine plot, now let us see how to save
+the plot for future use so that you can embed the plot in your
+reports.
+
+.. #[Puneeth: All this is known stuff. You don't have to elaborate so
+.. much on it. Just say, let us plot sin function from -3 pi to 3
+.. pi. Show the commands, and be done with it. ]
+
+{{{ switch to next slide, savefig() }}}
+
+{{{ Switch the focus to IPython interpreter window }}}
+
+For saving the plot, we will use ``savefig()`` function, and it has to be
+done with the plot window open. The statement is, ::
+
+  savefig('/home/fossee/sine.png')
+
+Notice that ``savefig`` function takes one argument which is the
+filename. The last 3 characters after the ``.`` in the filename is the
+extension or type of the file which determines the format in which you
+want to save.
+
+.. #[Puneeth: removed mention of string]
+
+.. #[[Anoop: I think this treatment is better :) ]]
+
+{{{ Highlight the /home/fossee part using mouse movements }}}
+
+Also, note that we gave the full path or the absolute path to which we
+want to save the file.
+
+{{{ Highlight the .png part using mouse movements }}}
+
+Here I have used an extension ``.png`` which means I want to save the
+image as a PNG file.
+
+Now let us locate ``sine.png`` file saved. We saved the file to
+``/home/fossee`` so let us navigate to ``/home/fossee`` using the
+file browser.
+
+{{{ Open the browser, navigate to /home/fossee and highlight the file
+sine.png }}}
+
+Yes, the file ``sine.png`` is here and let us check it.
+
+{{{ Open the file sine.png and show it for two-three seconds and then
+close it and return to IPython interpreter, make sure the plot window
+is still open, also don't close the file browser window }}}
+
+{{{ switch to next slide, More on savefig() }}}
+
+So in-order to save a plot, we use ``savefig`` function. ``savefig``
+can save the plot in many formats, such as pdf - portable document
+format, ps - post script, eps - encapsulated post script, svg -
+scalable vector graphics, png - portable network graphics which
+support transparency etc.
+
+.. #[[slide must give the extensions for the files - Anoop]]
+
+{{{ switch to next slide, exercise 1 }}}
+
+Let us now try to save the plot in eps format. ``eps`` stands for
+encapsulated post script, and it can be embedded in your latex
+documents. Pause here and try to figure it out yourself.
+
+{{{ Switch focus to the already open plot window }}}
+
+We still have the sine plot with us, and now let us save the plot as
+``sine.eps``.
+
+{{{ switch to next slide, solution 1 }}}
+
+{{{ Switch focus to IPython interpreter }}}
+
+Now, We will save the plot using the function ``savefig`` ::
+
+  savefig('/home/fossee/sine.eps')
+
+{{{ Switch focus to file browser window }}}
+
+Now let us go to ``/home/fossee`` and see the new file created.
+
+{{{ Highlight the file sine.eps with a single mouse click for 2
+seconds and then double click and open the file }}}
+
+Yes! the new file ``sine.eps`` is here.
+
+{{{ switch to next slide, exercise 2 }}}
+
+Now you may try saving the same in pdf, ps, svg formats.
+
+{{{ Switch to summary slide }}}
+
+This brings us to the end of this tutorial, in this tutorial we
+learned to save plots using the function ``savefig()``. Saving the
+plots in different formats and locating the files in the file system.
+
+{{{ switch to Thank you slide }}}
+
+Thank you!