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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}