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+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Tutorial slides on Python.
+%
+% Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>
+% Copyright (c) 2005-2008, Prabhu Ramachandran
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\documentclass[14pt,compress]{beamer}
+%\documentclass[draft]{beamer}
+%\documentclass[compress,handout]{beamer}
+%\usepackage{pgfpages} 
+%\pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm]
+
+% Modified from: generic-ornate-15min-45min.de.tex
+\mode<presentation>
+{
+  \usetheme{Warsaw}
+  \useoutertheme{split}
+  \setbeamercovered{transparent}
+}
+
+\usepackage[english]{babel}
+\usepackage[latin1]{inputenc}
+%\usepackage{times}
+\usepackage[T1]{fontenc}
+
+% Taken from Fernando's slides.
+\usepackage{ae,aecompl}
+\usepackage{mathpazo,courier,euler}
+\usepackage[scaled=.95]{helvet}
+
+\definecolor{darkgreen}{rgb}{0,0.5,0}
+
+\usepackage{listings}
+\lstset{language=Python,
+    basicstyle=\ttfamily,
+    commentstyle=\color{red}\itshape,
+  stringstyle=\color{darkgreen},
+  showstringspaces=false,
+  keywordstyle=\color{blue}\bfseries}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Macros
+\setbeamercolor{emphbar}{bg=blue!20, fg=black}
+\newcommand{\emphbar}[1]
+{\begin{beamercolorbox}[rounded=true]{emphbar} 
+      {#1}
+ \end{beamercolorbox}
+}
+\newcounter{time}
+\setcounter{time}{0}
+\newcommand{\inctime}[1]{\addtocounter{time}{#1}{\tiny \thetime\ m}}
+
+\newcommand{\typ}[1]{\texttt{#1}}
+
+\newcommand{\kwrd}[1]{ \texttt{\textbf{\color{blue}{#1}}}  }
+
+%%% This is from Fernando's setup.
+% \usepackage{color}
+% \definecolor{orange}{cmyk}{0,0.4,0.8,0.2}
+% % Use and configure listings package for nicely formatted code
+% \usepackage{listings}
+% \lstset{
+%    language=Python,
+%    basicstyle=\small\ttfamily,
+%    commentstyle=\ttfamily\color{blue},
+%    stringstyle=\ttfamily\color{orange},
+%    showstringspaces=false,
+%    breaklines=true,
+%    postbreak = \space\dots
+% }
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Title page
+\title[Basic Python]{Python:\\Modular Code, Handling Files and Objects}
+
+\author[FOSSEE Team] {Asokan Pichai\\Prabhu Ramachandran}
+
+\institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
+\date[] {10, October 2009}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
+%\logo{\pgfuseimage{iitmlogo}}
+
+
+%% Delete this, if you do not want the table of contents to pop up at
+%% the beginning of each subsection:
+\AtBeginSubsection[]
+{
+  \begin{frame}<beamer>
+    \frametitle{Outline}
+    \tableofcontents[currentsection,currentsubsection]
+  \end{frame}
+}
+
+
+% If you wish to uncover everything in a step-wise fashion, uncomment
+% the following command: 
+%\beamerdefaultoverlayspecification{<+->}
+
+%\includeonlyframes{current,current1,current2,current3,current4,current5,current6}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% DOCUMENT STARTS
+\begin{document}
+
+\begin{frame}
+  \titlepage
+\end{frame}
+
+\section{Python}
+
+\begin{frame}
+  {Problem set 3}
+  As you can guess, idea is to use \kwrd{for}!
+\end{frame}
+
+\begin{frame}{Problem 3.1}
+  Which of the earlier problems is simpler when we use \kwrd{for} instead of \kwrd{while}? 
+\end{frame}
+
+\begin{frame}{Problem 3.2}
+  Given an empty chessboard and one Bishop placed in any square, say (r, c), generate the list of all squares the Bishop could move to.
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Problem 3.3}
+
+  Given two real numbers \typ{a, b}, and an integer \typ{N}, write a
+  function named \typ{linspace( a, b, N)} that returns an ordered list
+  of \typ{N} points starting with \typ{a} and ending in \typ{b} and
+  equally spaced.\\
+
+  For example, \typ{linspace(0, 5, 11)}, should return, \\
+\begin{lstlisting}
+[ 0.0 ,  0.5,  1.0 ,  1.5,  2.0 ,  2.5,  
+  3.0 ,  3.5,  4.0 ,  4.5,  5.0 ]
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Problem 3.4a (optional)}
+
+Use the \typ{linspace} function and generate a list of N tuples of the form\\
+\typ{[($x_1$,f($x_1$)),($x_2$,f($x_2$)),\ldots,($x_N$,f($x_N$))]}\\for the following functions,\begin{itemize}
+  \item \typ{f(x) = sin(x)}
+  \item \typ{f(x) = sin(x) + sin(10*x)}.
+\end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Problem 3.4b (optional)}
+
+  Using the tuples generated earlier, determine the intervals where the roots of the functions lie.
+
+  \inctime{15}
+\end{frame}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% TIME: 15 m, running 185m 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\subsection{IO}
+
+\begin{frame}[fragile]
+  \frametitle{Simple tokenizing and parsing}
+  \begin{lstlisting}
+s = """The quick brown fox jumped
+       over the lazy dog"""
+for word in s.split():
+    print word.capitalize()
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Problem 4.1}
+  Given a string like, ``1, 3-7, 12, 15, 18-21'', produce the list \\
+  \begin{lstlisting}
+    [1,3,4,5,6,7,12,15,18,19,20,21]
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{File handling}
+\begin{lstlisting}
+>>> f = open('/path/to/file_name')
+>>> data = f.read() # Read entire file.
+>>> line = f.readline() # Read one line.
+>>> f.close() # close the file.
+\end{lstlisting}
+Writing files
+\begin{lstlisting}
+>>> f = open('/path/to/file_name', 'w')
+>>> f.write('hello world\n')
+>>> f.close()
+\end{lstlisting}
+\begin{itemize}
+    \item Everything read or written is a string
+\end{itemize}
+\emphbar{Try \typ{file?} for more help}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{File and \kwrd{for}}
+\begin{lstlisting}
+>>> f = open('/path/to/file_name')
+>>> for line in f:
+...     print line
+...
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}{Problem 4.2}
+    The given file has lakhs of records in the form:\\
+    \typ{RGN;ID;NAME;MARK1;\ldots;MARK5;TOTAL;PFW}\\
+    Some entries may be empty.  Read the data from this file and print the
+    name of the student with the maximum total marks.
+\end{frame}
+
+\begin{frame}{Problem 4.3}
+    For the same data file compute the average marks in different
+    subjects, the student with the maximum mark in each subject and also
+    the standard deviation of the marks.  Do this efficiently.
+
+    \inctime{20}
+\end{frame}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% TIME: 20 m, running 205m 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\subsection{Modules}
+
+\begin{frame}[fragile]
+    {Modules}
+\begin{lstlisting}
+>>> sqrt(2)
+Traceback (most recent call last):
+  File "<stdin>", line 1, in <module>
+NameError: name 'sqrt' is not defined
+>>> import math        
+>>> math.sqrt(2)
+1.4142135623730951
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+    {Modules}
+  \begin{itemize}
+    \item The \kwrd{import} keyword ``loads'' a module
+    \item One can also use:
+      \begin{lstlisting}
+>>> from math import sqrt
+>>> from math import *
+      \end{lstlisting}    
+    \item What is the difference?
+    \item \alert{Use the later only in interactive mode}
+    \end{itemize}
+  \emphbar{Package hierarchies}
+      \begin{lstlisting}
+>>> from os.path import exists
+      \end{lstlisting}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Modules: Standard library}
+  \begin{itemize}
+  \item Very powerful, ``Batteries included''
+  \item Some standard modules:
+    \begin{itemize}
+    \item Math: \typ{math}, \typ{random}
+    \item Internet access: \typ{urllib2}, \typ{smtplib}
+    \item System, Command line arguments: \typ{sys}
+    \item Operating system interface: \typ{os}
+    \item Regular expressions: \typ{re}
+    \item Compression: \typ{gzip}, \typ{zipfile}, and \typ{tarfile}
+    \item And a whole lot more!
+    \end{itemize}
+  \item Check out the Python Library reference:
+    \url{http://docs.python.org/library/}
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+    {Modules of special interest}
+    \begin{description}[matplotlibfor2d]
+
+        \item[\typ{numpy}] Efficient, powerful numeric arrays
+
+        \item[\typ{matplotlib}] Easy, interactive, 2D plotting
+
+        \item[\typ{scipy}] statistics, optimization, integration, linear
+            algebra, Fourier transforms, signal and image processing,
+            genetic algorithms, ODE solvers, special functions, and more
+
+        \item[Mayavi] Easy, interactive, 3D plotting
+
+    \end{description}
+\end{frame}
+
+\begin{frame}[fragile]
+    {Creating your own modules}
+  \begin{itemize}
+  \item Define variables, functions and classes in a file with a
+    \typ{.py} extension
+  \item This file becomes a module!
+  \item Accessible when in the current directory
+  \item Use \typ{cd} in IPython to change directory
+
+  \item Naming your module
+      \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Modules: example}
+  \begin{lstlisting}
+# --- arith.py ---
+def gcd(a, b):
+    if a%b == 0: return b
+    return gcd(b, a%b)
+def lcm(a, b):
+    return a*b/gcd(a, b)
+# ------------------
+>>> import arith
+>>> arith.gcd(26, 65)
+13
+>>> arith.lcm(26, 65)
+130
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Problem 5.1}
+
+  Put all the functions you have written so far as part of the problems
+  into one module called \typ{iitb.py} and use this module from IPython.
+
+\inctime{20}
+\end{frame}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% TIME: 20 m, running 225m 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\subsection{Objects}
+\begin{frame}{Objects in Python}
+    \begin{itemize}
+        \item What is an Object? (Types and classes)
+        \item identity
+        \item type
+        \item method
+      \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Why are they useful?}
+  \small
+  \begin{lstlisting}
+for element in (1, 2, 3):
+    print element
+for key in {'one':1, 'two':2}:
+    print key
+for char in "123":
+    print char
+for line in open("myfile.txt"):
+    print line
+for line in urllib2.urlopen('http://site.com'):
+    print line
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}{And the winner is \ldots OBJECTS!}
+  All objects providing a similar inteface can be used the same way.\\
+  Functions (and others) are first-class objects. Can be passed to and returned from functions.
+  \inctime{10}
+\end{frame}
+
+\subsection{Coding Style in Python}
+\begin{frame}{Readability and Consistency}
+    \begin{itemize}
+        \item Readability Counts!-Code is read more often than its written.
+        \item Consistency!
+        \item Know when to be inconsistent.
+      \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Code Layout}
+  \begin{itemize}
+        \item Indentation
+        \item Tabs or Spaces??
+        \item Maximum Line Length
+        \item Blank Lines
+        \item Encodings
+   \end{itemize}
+\end{frame}
+
+\begin{frame}{Whitespaces in Expressions}
+  \begin{itemize}
+        \item When to use extraneous whitespaces??
+        \item When to avoid extra whitespaces??
+        \item Use one statement per line
+   \end{itemize}
+\end{frame}
+
+\begin{frame}{Comments}
+  \begin{itemize}
+        \item No comments better than contradicting comments
+        \item Block comments
+        \item Inline comments
+   \end{itemize}
+\end{frame}
+
+\begin{frame}{Docstrings}
+  \begin{itemize}
+        \item When to write docstrings?
+        \item Ending the docstrings
+        \item One liner docstrings
+   \end{itemize}
+\end{frame}
+\inctime{10}
+\end{document}