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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\bfseries,
+ 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:\\Advanced Python data structures, Functions and Debugging}
+
+\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}
+
+\subsection{Dictionary}
+\begin{frame}{Dictionary}
+ \begin{itemize}
+ \item aka associative arrays, key-value pairs, hashmaps, hashtables \ldots
+ \item \typ{ d = \{ ``Hitchhiker's guide'' : 42, ``Terminator'' : ``I'll be back''\}}
+ \item lists and tuples index: 0 \ldots n
+ \item dictionaries index using strings
+ \item aka key-value pairs
+ \item what can be keys?
+ \end{itemize}
+\end{frame}
+
+\begin{frame}{Dictionary \ldots }
+ \begin{itemize}
+ \item \alert{Unordered}
+ \begin{block}{Standard usage}
+ for key in dict:\\
+ <use> dict[key] \# => value
+ \end{block}
+ \item \typ{d.keys()} returns a list
+ \item can we have duplicate keys?
+ \end{itemize}
+ \inctime{5}
+\end{frame}
+
+\begin{frame} {Problem Set 2.1}
+ \begin{description}
+\item[2.1.1] You are given date strings of the form ``29, Jul 2009'', or ``4 January 2008''. In other words a number a string and another number, with a comma sometimes separating the items.Write a function that takes such a string and returns a tuple (yyyy, mm, dd) where all three elements are ints.
+ \item[2.1.2] Count word frequencies in a file.
+ \item[2.1.3] Find the most used Python keywords in your Python code (import keyword).
+\end{description}
+
+\inctime{10}
+\end{frame}
+
+\subsection{Set}
+\begin{frame}[fragile]
+ \frametitle{Set}
+ \begin{itemize}
+ \item Simplest container, mutable
+ \item No ordering, no duplicates
+ \item usual suspects: union, intersection, subset \ldots
+ \item >, >=, <, <=, in, \ldots
+ \end{itemize}
+ \begin{lstlisting}
+>>> f10 = set([1,2,3,5,8])
+>>> p10 = set([2,3,5,7])
+>>> f10|p10
+set([1, 2, 3, 5, 7, 8])
+>>> f10&p10
+set([2, 3, 5])
+>>> f10-p10
+set([8, 1])
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Set}
+ \begin{lstlisting}
+>>> p10-f10, f10^p10
+set([7]), set([1, 7, 8])
+>>> set([2,3]) < p10
+True
+>>> set([2,3]) <= p10
+True
+>>> 2 in p10
+True
+>>> 4 in p10
+False
+>>> len(f10)
+5
+\end{lstlisting}
+\inctime{5}
+\end{frame}
+
+
+\begin{frame}
+ \frametitle{Problem set 2.2}
+ \begin{description}
+ \item[2.2.1] Given a dictionary of the names of students and their marks, identify how many duplicate marks are there? and what are these?
+ \item[2.2.2] Given a string of the form ``4-7, 9, 12, 15'' find the numbers missing in this list for a given range.
+\end{description}
+\inctime{10}
+\end{frame}
+
+\subsection{Functions Reloaded!}
+\begin{frame}[fragile]
+ \frametitle{Advanced functions}
+ \begin{itemize}
+ \item default args
+ \item var args
+ \item keyword args
+ \item scope
+ \item \typ{global}
+ \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Functions: default arguments}
+ \small
+ \begin{lstlisting}
+def ask_ok(prompt, retries=4,
+ complaint='Yes or no!'):
+ while True:
+ ok = raw_input(prompt)
+ if ok in ('y', 'ye', 'yes'):
+ return True
+ if ok in ('n', 'no', 'nop',
+ 'nope'):
+ return False
+ retries = retries - 1
+ if retries < 0:
+ raise IOError, 'bad user'
+ print complaint
+ \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Functions: keyword arguments}
+ \small
+ \begin{lstlisting}
+def parrot(voltage, state='a stiff',
+ action='voom', type='Royal Blue'):
+ print "-- This parrot wouldn't", action,
+ print "if you supply", voltage, "Volts."
+ print "-- Lovely plumage, the", type
+ print "-- It's", state, "!"
+
+parrot(1000)
+parrot(action = 'VOOOOOM', voltage = 1000000)
+parrot('a thousand',
+ state = 'pushing up the daisies')
+parrot('a million', 'bereft of life', 'jump')
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Functions: arbitrary argument lists}
+ \begin{itemize}
+ \item Arbitrary number of arguments using \verb+*args+ or
+ \verb+*whatever+
+ \item Keyword arguments using \verb+**kw+
+ \item Given a tuple/dict how do you call a function?
+ \begin{itemize}
+ \item Using argument unpacking
+ \item For positional arguments: \verb+foo(*[5, 10])+
+ \item For keyword args: \verb+foo(**{'a':5, 'b':10})+
+ \end{itemize}
+ \end{itemize}
+\end{frame}
+
+ \begin{frame}[fragile]
+\begin{lstlisting}
+def foo(a=10, b=100):
+ print a, b
+def func(*args, **keyword):
+ print args, keyword
+# Unpacking:
+args = [5, 10]
+foo(*args)
+kw = {'a':5, 'b':10}
+foo(**kw)
+\end{lstlisting}
+ \inctime{15}
+\end{frame}
+
+\subsection{Functional programming}
+\begin{frame}[fragile]
+ \frametitle{Functional programming}
+What is the basic idea?\\
+Why is it interesting?\\
+\typ{map, reduce, filter}\\
+list comprehension\\
+generators
+ \inctime{15}
+\end{frame}
+
+\subsection{Debugging}
+\begin{frame}[fragile]
+ \frametitle{Errors}
+ \begin{lstlisting}
+>>> while True print 'Hello world'
+ File "<stdin>", line 1, in ?
+ while True print 'Hello world'
+ ^
+SyntaxError: invalid syntax
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Exceptions}
+ \begin{lstlisting}
+>>> print spam
+Traceback (most recent call last):
+ File "<stdin>", line 1, in <module>
+NameError: name 'spam' is not defined
+
+>>> 1 / 0
+Traceback (most recent call last):
+ File "<stdin>", line 1, in <module>
+ZeroDivisionError: integer division
+or modulo by zero
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Debugging effectively}
+
+ \begin{itemize}
+ \item \kwrd{print} based strategy
+ \item Process: Hypothesis, test, refine, rinse-repeat
+ \item Using \typ{\%debug} and \typ{\%pdb} in IPython
+ \end{itemize}
+ \inctime{15}
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{Debugging: example}
+\small
+\begin{lstlisting}
+>>> import pdb
+>>> import mymodule
+>>> pdb.run('mymodule.test()')
+> <string>(1)<module>()
+(Pdb) continue
+Traceback (most recent call last):
+ File "<stdin>", line 1, in <module>
+ File "/usr/lib/python2.6/pdb.py", line 1207, in run
+ Pdb().run(statement, globals, locals)
+ File "/usr/lib/python2.6/bdb.py", line 368, in run
+ exec cmd in globals, locals
+ File "<string>", line 1, in <module>
+ File "mymodule.py", line 2, in test
+ print spam
+NameError: global name 'spam' is not defined
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{Debugging in IPython}
+\small
+\begin{lstlisting}
+In [1]: %pdb
+Automatic pdb calling has been turned ON
+In [2]: import mymodule
+In [3]: mymodule.test()
+----------------------------------------------
+NameError Traceback (most recent call last)
+/media/python/iitb/workshops/day1/<ipython console> in <module>()
+/media/python/iitb/workshops/day1/mymodule.pyc in test()
+ 1 def test():
+----> 2 print spam
+NameError: global name 'spam' is not defined
+> /media/python/iitb/workshops/day1/mymodule.py(2)test()
+ 0 print spam
+ipdb>
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{Debugging: Exercise}
+\end{frame}
+
+\end{document}