
diff -r d4ad532525a2 -r c4e25269a86c day2/session5.tex
--- a/day2/session5.tex	Fri Nov 06 17:56:22 2009 +0530
+++ b/day2/session5.tex	Fri Nov 06 18:33:08 2009 +0530
@@ -1,33 +1,48 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%Tutorial slides on Python.
+% Tutorial slides on Python.
 %
 % Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>
 % Copyright (c) 2005-2009, Prabhu Ramachandran
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-\documentclass[14pt,compress]{beamer}
-%\documentclass[draft]{beamer}
-%\documentclass[compress,handout]{beamer}
-%\usepackage{pgfpages} 
-%\pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm]
+\documentclass[compress,14pt]{beamer}
+% \documentclass[handout]{beamer}
+% \usepackage{pgfpages}
+% \pgfpagesuselayout{4 on 1}[a4paper,border, shrink=5mm,landscape]
+\usepackage{tikz}
+\newcommand{\hyperlinkmovie}{}
+%\usepackage{movie15}
 
-% Modified from: generic-ornate-15min-45min.de.tex
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Note that in presentation mode 
+% \paperwidth  364.19536pt
+% \paperheight 273.14662pt
+% h/w = 0.888
+
+
 \mode<presentation>
 {
   \usetheme{Warsaw}
+  %\usetheme{Boadilla}
+  %\usetheme{default}
   \useoutertheme{infolines}
   \setbeamercovered{transparent}
 }
 
+% To remove navigation symbols
+\setbeamertemplate{navigation symbols}{}
+
+\usepackage{amsmath}
 \usepackage[english]{babel}
 \usepackage[latin1]{inputenc}
-%\usepackage{times}
+\usepackage{times}
 \usepackage[T1]{fontenc}
 
 % Taken from Fernando's slides.
 \usepackage{ae,aecompl}
 \usepackage{mathpazo,courier,euler}
 \usepackage[scaled=.95]{helvet}
+\usepackage{pgf}
 
 \definecolor{darkgreen}{rgb}{0,0.5,0}
 
@@ -40,50 +55,65 @@
   keywordstyle=\color{blue}\bfseries}
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-% Macros
+% My Macros
+\setbeamercolor{postit}{bg=yellow,fg=black}
 \setbeamercolor{emphbar}{bg=blue!20, fg=black}
 \newcommand{\emphbar}[1]
 {\begin{beamercolorbox}[rounded=true]{emphbar} 
       {#1}
  \end{beamercolorbox}
 }
+%{\centerline{\fcolorbox{gray!50} {blue!10}{
+%\begin{minipage}{0.9\linewidth}
+%    {#1} 
+%\end{minipage}
+%    }}}
+
+\newcommand{\myemph}[1]{\structure{\emph{#1}}}
+\newcommand{\PythonCode}[1]{\lstinline{#1}}
+
+\newcommand{\tvtk}{\texttt{tvtk}}
+\newcommand{\mlab}{\texttt{mlab}}
+\newcommand{\typ}[1]{\lstinline{#1}}
 \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}}}  }
+\newcommand{\inctime}[1]{\addtocounter{time}{#1}{\vspace*{0.1in}\tiny \thetime\ m}}
 
-%%% 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
-% }
+\newcommand\BackgroundPicture[1]{%
+  \setbeamertemplate{background}{%
+      \parbox[c][\paperheight]{\paperwidth}{%
+      \vfill \hfill
+ \hfill \vfill
+}}}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Configuring the theme
+%\setbeamercolor{normal text}{fg=white}
+%\setbeamercolor{background canvas}{bg=black}
+
 
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % Title page
-\title[Exercises]{Exercises}
+\title[Python Development]{Python Development}
 
 \author[FOSSEE] {FOSSEE}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {1 November, 2009\\Day 2, Session 4}
+\date[] {1 November, 2009\\Day 2, Session 3}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-%\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
-%\logo{\pgfuseimage{iitmlogo}}
+%\pgfdeclareimage[height=0.75cm]{iitblogo}{iitblogo}
+%\logo{\pgfuseimage{iitblogo}}
 
+\AtBeginSection[]
+{
+  \begin{frame}<beamer>
+    \frametitle{Outline}
+      \Large
+    \tableofcontents[currentsection,currentsubsection]
+  \end{frame}
+}
 
 %% Delete this, if you do not want the table of contents to pop up at
 %% the beginning of each subsection:
@@ -95,109 +125,438 @@
   \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}
-
+\AtBeginSection[]
+{
+  \begin{frame}<beamer>
+    \frametitle{Outline}
+    \tableofcontents[currentsection,currentsubsection]
+  \end{frame}
+}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % DOCUMENT STARTS
 \begin{document}
 
 \begin{frame}
-  \titlepage
+  \maketitle
+\end{frame}
+
+\section{Tests: Getting started}
+\begin{frame}[fragile] 
+  \frametitle{gcd revisited!}
+  \begin{itemize}
+  \item Open gcd.py
+  \end{itemize}  
+\begin{lstlisting}
+    def gcd(a, b):
+        if a % b == 0: 
+            return b
+        return gcd(b, a%b)
+
+    print gcd(15, 65)
+    print gcd(16, 76)
+\end{lstlisting}
+  \begin{itemize}
+  \item python gcd.py
+  \end{itemize}
 \end{frame}
 
-\begin{frame}{Problem 1.1}
-  The aliquot of a number is defined as: the sum of the \emph{proper} divisors of the number. \\For example: 
-\center{aliquot(12) = 1 + 2 + 3 + 4 + 6 = 16.}\\
-  Write a function that returns the aliquot number of a given number. 
+\begin{frame}[fragile] 
+  \frametitle{Find lcm using our gcd module}
+  \begin{itemize}
+  \item Open lcm.py  
+  \item $lcm = \frac{a*b}{gcd(a,b)}$
+  \end{itemize}  
+\begin{lstlisting}
+    from gcd import gcd    
+    def lcm(a, b):
+        return (a * b) / gcd(a, b)
+    
+    print lcm(14, 56)
+\end{lstlisting}
+  \begin{itemize}
+  \item python lcm.py
+  \end{itemize}
+  \begin{lstlisting}
+5
+4
+56
+  \end{lstlisting}    
 \end{frame}
 
-\begin{frame}{Problem 1.2}
-  Pair of numbers (a, b) is said to be \alert{amicable} if aliquot number of a is b and aliquot number of b is a.\\
-  Example: \texttt{220, 284}\\
-  Write a program that prints all four digit amicable pairs.
-  
-\inctime{20}
+\begin{frame}[fragile] 
+  \frametitle{Writing stand-alone module}  
+Edit gcd.py file to:
+\begin{lstlisting}
+    def gcd(a, b):
+        if a % b == 0: 
+            return b
+        return gcd(b, a%b)
+
+    if __name__ == "__main__":        
+        print gcd(15, 65)
+        print gcd(16, 76)
+\end{lstlisting}
+  \begin{itemize}
+  \item python gcd.py
+  \item python lcm.py
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{More use of main}
+  For automating tests.
+  \begin{lstlisting}
+if __name__ == '__main__':
+    for line in open('numbers.txt'):
+        numbers = line.split()
+        x = int(numbers[0])
+        y = int(numbers[1])
+        result = (int(numbers[2]))
+        assert gcd(x, y) == result
+  \end{lstlisting}  
+\end{frame}
+
+\section{Coding Style}
+\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}{Problem 2}
-%%   Given an empty chessboard and one Bishop placed in any s%quare, say (r, c), generate the list of all squares the Bi%shop could move to.
-
-%% \end{frame}
+\begin{frame}[fragile] \frametitle{A question of good style}
+  \begin{lstlisting}
+    amount = 12.68
+    denom = 0.05
+    nCoins = round(amount/denom)
+    rAmount = nCoins * denom
+  \end{lstlisting}
+  \pause
+  \begin{block}{Style Rule \#1}
+    Naming is 80\% of programming
+  \end{block}
+\end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Problem Set 2}
-  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}
-\inctime{10}
+  \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}
+More information at PEP8: http://www.python.org/dev/peps/pep-0008/
+\inctime{5}
 \end{frame}
 
-\begin{frame} 
-  \frametitle{Problem Set 3}
-  \begin{description}
-    \item[3.1] Count word frequencies in a file.
-\end{description}
-\inctime{5}
+\section{Debugging}
+\subsection{Errors and Exceptions}
+\begin{frame}[fragile]
+ \frametitle{Errors}
+ \begin{lstlisting}
+In []: while True print 'Hello world'
+ \end{lstlisting}
+\pause
+  \begin{lstlisting}
+  File "<stdin>", line 1, in ?
+    while True print 'Hello world'
+                   ^
+SyntaxError: invalid syntax
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Exceptions}
+ \begin{lstlisting}
+In []: print spam
+\end{lstlisting}
+\pause
+\begin{lstlisting}
+Traceback (most recent call last):
+  File "<stdin>", line 1, in <module>
+NameError: name 'spam' is not defined
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+ \frametitle{Exceptions}
+ \begin{lstlisting}
+In []: 1 / 0
+\end{lstlisting}
+\pause
+\begin{lstlisting}
+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{Problem set 4}
-  Central difference
-  \begin{equation*}
-  \frac{sin(x+h)-sin(x-h)}{2h}
-  \end{equation*}
+  \frametitle{Handling Exceptions}
+  Python uses \typ{try} and \typ{except} clause.
+  %%Revisiting the raw\_input
   \begin{lstlisting}
-  In []: x = linspace(0, 2*pi, 100)
-  In []: y = sin(x)
-  In []: deltax = x[1] - x[0]
+a = raw_input('Enter number(Q to quit):')
+try:
+    num = int(a)
+    print num
+except:
+    if a == 'Q':
+        print 'Exiting...'
+    else:
+        print 'Wrong input!'      
   \end{lstlisting}
-  \pause
-    \begin{enumerate}
-      \item Given this, get the finite difference of sin in the range 0 to 2*pi
-    \end{enumerate}
+  
+  
+\end{frame}
+
+%% \begin{frame}[fragile]
+%%   \frametitle{Solving it with \typ{try} and \typ{except}}
+%% \vspace{-0.2in}
+%%   \begin{lstlisting}
+%% highest = 0
+%% for record in open('sslc1.txt'):
+%%     fields = record.split(';')
+%%     try:
+%%         total = 0
+%%         for score_str in fields[3:8]:
+%%             score = int(score_str)
+%%             total += score
+%%         if total > highest:
+%%             highest = total
+%%     except:        
+%%         pass
+%% print highest
+%%   \end{lstlisting}
+%% \end{frame}
+\subsection{Strategy}
+\begin{frame}[fragile]
+    \frametitle{Debugging effectively}
+    \begin{itemize}
+        \item \typ{print} based strategy
+        \item Process:
+    \end{itemize}
+\begin{center}
+\pgfimage[interpolate=true,width=5cm,height=5cm]{DebugginDiagram.png}
+\end{center}
 \end{frame}
 
-\begin{frame}
-  \frametitle{Problem Set 5}
-  \begin{itemize}
-      \item[5.1] Write a function that plots any regular n-gon given \typ{n}.
-      \item[5.2] Consider the logistic map, $f(x) = kx(1-x)$, plot it for
-          $k=2.5, 3.5$ and $4$ in the same plot.
-\end{itemize}
+\begin{frame}[fragile]
+    \frametitle{Debugging effectively}
+    \begin{itemize}
+      \item Using \typ{\%debug} in IPython
+    \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{Debugging in IPython}
+\small
+\begin{lstlisting}
+In []: import mymodule
+In []: mymodule.test()
+---------------------------------------------
+NameError   Traceback (most recent call last)
+<ipython console> in <module>()
+mymodule.py in test()
+      1 def test():
+----> 2     print spam
+NameError: global name 'spam' is not defined
+
+In []: %debug
+> mymodule.py(2)test()
+      0     print spam
+ipdb> 
+\end{lstlisting}
+\inctime{15} 
+\end{frame}
+
+\subsection{Exercise}
+\begin{frame}[fragile]
+\frametitle{Debugging: Exercise}
+\small
+\begin{lstlisting}
+science = {}
+
+for record in open('sslc1.txt'):
+    fields = record.split(';')
+    region_code = fields[0].strip()
+
+    score_str = fields[6].strip()
+    score = int(score_str) if score_str != 'AA' 
+                           else 0
+
+    if score > 90:
+        science[region_code] += 1
+
+pie(science.values(), labels=science.keys())
+savefig('science.png')
+\end{lstlisting}
+\inctime{10}
 \end{frame}
 
-\begin{frame}[fragile] 
-\frametitle{Problem Set 5}
-  \begin{columns}
-    \column{0.6\textwidth}
-    \small{
+%% \begin{frame}
+%%     \frametitle{Testing}
+   
+%%     \begin{itemize}
+%%         \item Writing tests is really simple!
+
+%%         \item Using nose.
+
+%%         \item Example!
+%%     \end{itemize}
+%% \end{frame}
+
+\section{Test Driven Approach}
+\begin{frame}
+    \frametitle{Need for Testing!}
+   
     \begin{itemize}
-      \item[3] Consider the iteration $x_{n+1} = f(x_n)$ where $f(x) = kx(1-x)$.  Plot the successive iterates of this process as explained below. 
-    \end{itemize}}
-    \column{0.35\textwidth}
-    \hspace*{-0.5in}
-  \includegraphics[height=1.6in, interpolate=true]{data/cobweb}  
-\end{columns}
+        \item Quality
+        \item Regression
+        \item Documentation
+    \end{itemize}
+    %% \vspace*{0.25in}
+    %% \emphbar{It is to assure that section of code is working as it is supposed to work}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Example}
+    \begin{block}{Problem Statement}
+      Write a function to check whether a given input
+      string is a palindrome.
+    \end{block}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Function: palindrome.py}
+\begin{lstlisting}    
+def is_palindrome(input_str):
+  return input_str == input_str[::-1]
+\end{lstlisting}    
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Test for the palindrome: palindrome.py}
+\begin{lstlisting}    
+def test_function_normal_words():
+  input = "noon"
+  assert is_palindrome(input) == True
+
+if __name__ == "main'':
+  test_function_normal_words()
+\end{lstlisting}    
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Running the tests.}
+\begin{lstlisting}    
+$ nosetests palindrome.py 
+.
+----------------------------------------------
+Ran 1 test in 0.001s
+
+OK
+\end{lstlisting}    
 \end{frame}
 
+\begin{frame}[fragile]
+    \frametitle{Exercise: Including new tests.}
+\begin{lstlisting}    
+def test_function_ignore_cases_words():
+  input = "Noon"
+  assert is_palindrome(input) == True
+\end{lstlisting}
+     \vspace*{0.25in}
+     Check\\
+     \PythonCode{$ nosetests palindrome.py} \\
+     \begin{block}{Task}
+     Tweak the code to pass this test.
+     \end{block}
+\end{frame}
+
+%\begin{frame}[fragile]
+%    \frametitle{Lets write some test!}
+%\begin{lstlisting}    
+%#for form of equation y=mx+c
+%#given m and c for two equation,
+%#finding the intersection point.
+%def intersect(m1,c1,m2,c2):
+%    x = (c2-c1)/(m1-m2)
+%    y = m1*x+c1
+%    return (x,y)
+%\end{lstlisting}
+%
+%Create a simple test for this
+%
+%function which will make it fail.
+%
+%\inctime{15} 
+%\end{frame}
+%
+
+%% \begin{frame}[fragile]
+%%     \frametitle{Exercise}
+%%     Based on Euclid's algorithm:
+%%     \begin{center}
+%%     $gcd(a,b)=gcd(b,b\%a)$
+%%     \end{center}
+%%     gcd function can be written as:
+%%     \begin{lstlisting}
+%%     def gcd(a, b):
+%%       if a%b == 0: return b
+%%       return gcd(b, a%b)
+%%     \end{lstlisting}
+%%     \vspace*{-0.15in}
+%%     \begin{block}{Task}
+%%       \begin{itemize}
+%%       \item Write at least 
+%%         two tests for above mentioned function.
+%%       \item Write a non recursive implementation
+%%       of gcd(), and test it using already 
+%%       written tests.
+%%       \end{itemize}
+%%     \end{block}
+    
+%% \inctime{15} 
+%% \end{frame}
+
 \begin{frame}
-  \frametitle{Problem Set 5.3}
-  Plot the cobweb plot as follows:
-  \begin{enumerate}
-    \item Start at $(x_0, 0)$ ($\implies$ i=0)
-    \item Draw a line to $(x_i, f(x_i))$
-    \item Set $x_{i+1} = f(x_i)$
-    \item Draw a line to $(x_{i+1}, x_{i+1})$
-    \item $(i\implies i+1)$ 
-    \item Repeat from 2 for as long as you want 
-  \end{enumerate}
-\inctime{20}
+  \frametitle{Summary}
+We have coverd:
+  \begin{itemize}
+  \item Following and Resolving Error Messages.
+  \item Exceptions.
+  \item Handling exceptions
+  \item Approach for Debugging.
+  \item Writting and running tests.
+  \end{itemize}
 \end{frame}
 
 \end{document}




