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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}