# HG changeset patch # User Puneeth Chaganti # Date 1256726138 -19800 # Node ID 1575143284cdac56d3333e5a9c7b3552de80a749 # Parent 78ce38a1e383718086dc3527316a313d37785c59# Parent da426ad6f0a95bc6edcae56825ea7f33c071a2c2 Merged with mainline. diff -r 78ce38a1e383 -r 1575143284cd day1/session3.tex --- a/day1/session3.tex Wed Oct 28 16:05:14 2009 +0530 +++ b/day1/session3.tex Wed Oct 28 16:05:38 2009 +0530 @@ -126,6 +126,7 @@ %% % You might wish to add the option [pausesections] %% \end{frame} +\section{Statistics} \begin{frame} \frametitle{More on data processing} \begin{block}{} @@ -178,8 +179,10 @@ \item Pass/Fail (P/F) \item Withdrawn (W) \end{itemize} + \inctime{5} \end{frame} +\subsection{Data processing} \begin{frame}[fragile] \frametitle{File reading and parsing \ldots} \begin{lstlisting} @@ -188,22 +191,23 @@ \end{lstlisting} \end{frame} +\subsection{Dictionary} \begin{frame}[fragile] \frametitle{Dictionary: Introduction} \begin{itemize} \item lists index: 0 \ldots n \item dictionaries index using strings \end{itemize} -\begin{block}{Example} + \begin{block}{Example} d = \{ ``Hitchhiker's guide'' : 42, ``Terminator'' : ``I'll be back''\}\\ d[``Terminator''] => ``I'll be back'' -\end{block} + \end{block} \end{frame} \begin{frame}[fragile] \frametitle{Dictionary: Introduction} -\begin{lstlisting} + \begin{lstlisting} In [1]: d = {"Hitchhiker's guide" : 42, "Terminator" : "I'll be back"} @@ -215,24 +219,24 @@ In [4]: "Guido" in d Out[4]: False -\end{lstlisting} + \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Dictionary: Introduction} -\begin{lstlisting} + \begin{lstlisting} In [5]: d.keys() Out[5]: ['Terminator', "Hitchhiker's guide"] In [6]: d.values() Out[6]: ["I'll be back", 42] -\end{lstlisting} + \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{enumerate: Iterating through list indices} -\begin{lstlisting} + \begin{lstlisting} In [1]: names = ["Guido","Alex", "Tim"] In [2]: for i, name in enumerate(names): @@ -241,15 +245,16 @@ 0 Guido 1 Alex 2 Tim -\end{lstlisting} + \end{lstlisting} + \inctime{5} \end{frame} \begin{frame}[fragile] \frametitle{Dictionary: Building parsed data} - Let our dictionary be: - \begin{lstlisting} + Let our dictionary be: + \begin{lstlisting} science = {} # is an empty dictionary - \end{lstlisting} + \end{lstlisting} \end{frame} \begin{frame}[fragile] @@ -291,6 +296,7 @@ \end{lstlisting} \end{frame} +\subsection{Visualizing the data} \begin{frame}[fragile] \frametitle{Pie charts} \small @@ -308,6 +314,7 @@ \includegraphics[height=2in, interpolate=true]{data/science} \column{0.8\textwidth} \end{columns} + \inctime{5} \end{frame} \begin{frame}[fragile] @@ -381,6 +388,7 @@ \includegraphics[height=3in, interpolate=true]{data/all_regions} \end{frame} +\subsection{Obtaining stastics} \begin{frame}[fragile] \frametitle{Obtaining statistics} \begin{lstlisting} @@ -395,6 +403,7 @@ print "Standard Deviation: ", std(math_scores) \end{lstlisting} + \inctime{15} \end{frame} \begin{frame}[fragile] diff -r 78ce38a1e383 -r 1575143284cd day1/session4.tex --- a/day1/session4.tex Wed Oct 28 16:05:14 2009 +0530 +++ b/day1/session4.tex Wed Oct 28 16:05:38 2009 +0530 @@ -136,14 +136,16 @@ \begin{frame}[fragile] \frametitle{Matrices: Initializing} \begin{lstlisting} -In []: A = ([[5, 2, 4], - [-3, 6, 2], - [3, -3, 1]]) - +In []: A = matrix([[ 1, 1, 2, -1], + [ 2, 5, -1, -9], + [ 2, 1, -1, 3], + [ 1, -3, 2, 7]]) In []: A -Out[]: [[5, 2, 4], - [-3, 6, 2], - [3, -3, 1]] +Out[]: +matrix([[ 1, 1, 2, -1], + [ 2, 5, -1, -9], + [ 2, 1, -1, 3], + [ 1, -3, 2, 7]]) \end{lstlisting} \end{frame} @@ -153,10 +155,11 @@ \frametitle{Transpose of a Matrix} \begin{lstlisting} In []: linalg.transpose(A) -Out[]: -matrix([[ 5, -3, 3], - [ 2, 6, -3], - [ 4, 2, 1]]) +Out[]: +matrix([[ 1, 2, 2, 1], + [ 1, 5, 1, -3], + [ 2, -1, -1, 2], + [-1, -9, 3, 7]]) \end{lstlisting} \end{frame} @@ -164,22 +167,23 @@ \frametitle{Sum of all elements} \begin{lstlisting} In []: linalg.sum(A) -Out[]: 17 +Out[]: 12 \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Matrix Addition} \begin{lstlisting} -In []: B = matrix([[3,2,-1], - [2,-2,4], - [-1, 0.5, -1]]) - -In []: linalg.add(A, B) +In []: B = matrix([[3,2,-1,5], + [2,-2,4,9], + [-1,0.5,-1,-7], + [9,-5,7,3]]) +In []: linalg.add(A,B) Out[]: -matrix([[ 8. , 4. , 3. ], - [-1. , 4. , 6. ], - [ 2. , -2.5, 0. ]]) +matrix([[ 4. , 3. , 1. , 4. ], + [ 4. , 3. , 3. , 0. ], + [ 1. , 1.5, -2. , -4. ], + [ 10. , -8. , 9. , 10. ]]) \end{lstlisting} \end{frame} @@ -188,9 +192,10 @@ \begin{lstlisting} In []: linalg.multiply(A, B) Out[]: -matrix([[ 15. , 4. , -4. ], - [ -6. , -12. , 8. ], - [ -3. , -1.5, -1. ]]) +matrix([[ 3. , 2. , -2. , -5. ], + [ 4. , -10. , -4. , -81. ], + [ -2. , 0.5, 1. , -21. ], + [ 9. , 15. , 14. , 21. ]]) \end{lstlisting} \end{frame} @@ -200,9 +205,10 @@ \begin{lstlisting} In []: linalg.inv(A) Out[]: -array([[ 0.28571429, -0.33333333, -0.47619048], - [ 0.21428571, -0.16666667, -0.52380952], - [-0.21428571, 0.5 , 0.85714286]]) +matrix([[-0.5 , 0.55, -0.15, 0.7 ], + [ 0.75, -0.5 , 0.5 , -0.75], + [ 0.5 , -0.15, -0.05, -0.1 ], + [ 0.25, -0.25, 0.25, -0.25]]) \end{lstlisting} \end{small} \end{frame} @@ -211,7 +217,7 @@ \frametitle{Determinant} \begin{lstlisting} In []: det(A) -Out[]: 42.0 +Out[66]: 80.0 \end{lstlisting} \end{frame} @@ -221,10 +227,11 @@ \begin{lstlisting} In []: linalg.eig(A) Out[]: -(array([ 7., 2., 3.]), - matrix([[-0.57735027, 0.42640143, 0.37139068], - [ 0.57735027, 0.63960215, 0.74278135], - [-0.57735027, -0.63960215, -0.55708601]])) +(array([ 11.41026155, 3.71581643, -0.81723144, -2.30884654]), + matrix([[ 0.12300187, -0.53899627, 0.63269982, 0.56024583], + [ 0.8225266 , -0.67562403, -0.63919634, -0.20747251], + [-0.04763219, -0.47575453, -0.3709497 , -0.80066041], + [-0.55321941, -0.16331814, -0.23133374, 0.04497415]])) \end{lstlisting} \end{small} \end{frame} @@ -232,8 +239,8 @@ \begin{frame}[fragile] \frametitle{Computing Norms} \begin{lstlisting} - In []: linalg.norm(A) - Out[]: 10.63014581273465 +In []: linalg.norm(A) +Out[]: 14.0 \end{lstlisting} \end{frame} @@ -243,14 +250,16 @@ \begin{lstlisting} In []: linalg.svd(A) Out[]: -(matrix([[-0.13391246, -0.94558684, -0.29653495], - [ 0.84641267, -0.26476432, 0.46204486], - [-0.51541542, -0.18911737, 0.83581192]]), - array([ 7.96445022, 7. , 0.75334767]), - matrix([[-0.59703387, 0.79815896, 0.08057807], - [-0.64299905, -0.41605821, -0.64299905], - [-0.47969029, -0.43570384, 0.7616163 ]])) - \end{lstlisting} +(matrix([[-0.08588113, 0.29164297, -0.74892678, 0.58879325], + [-0.79093255, 0.39530483, -0.11188116, -0.45347812], + [ 0.1523891 , 0.78799358, 0.51966138, 0.29290907], + [ 0.58636823, 0.37113957, -0.39565558, -0.60156827]]), + array([ 13.17656506, 3.76954116, 2.79959047, 0.57531379]), + matrix([[-0.05893795, -0.42858358, 0.12442679, 0.89295039], + [ 0.80364672, 0.51537891, 0.03774111, 0.29514767], + [-0.11752501, 0.14226922, -0.96333552, 0.19476145], + [-0.58040171, 0.72832696, 0.23468759, 0.27855956]])) +\end{lstlisting} \end{small} \end{frame} @@ -282,8 +291,6 @@ In []: b = matrix([[1], [-2], [0]]) In []: x = linalg.solve(A, b) In []: Ax = dot(A, x) - In []: allclose(Ax, b) - Out[]: True \end{lstlisting} \end{frame} @@ -295,13 +302,44 @@ array([[ 1.], [-2.], [-2.]]) +\end{lstlisting} +\end{frame} +\begin{frame}[fragile] +\frametitle{Let's check!} +\begin{lstlisting} In []: Ax Out[]: matrix([[ 1.00000000e+00], [ -2.00000000e+00], [ 2.22044605e-16]]) \end{lstlisting} +\begin{block}{} +The last term in the matrix is actually \alert{0}!\\ +We can use \kwrd{allclose()} to check. +\end{block} +\begin{lstlisting} +In []: allclose(Ax, b) +Out[]: True +\end{lstlisting} +\end{frame} + +\subsection{Exercises} + +\begin{frame}[fragile] +\frametitle{Problem} + +\end{frame} + +\begin{frame}[fragile] +\frametitle{Problem} +Solve the set of equations: +\begin{align*} + x + y + 2z -w & = 3\\ + 2x + 5y - z - 9w & = -3\\ + 2x + y -z + 3w & = -11 \\ + x - 3y + 2z + 7w & = -5\\ +\end{align*} \end{frame} \section{Summary} diff -r 78ce38a1e383 -r 1575143284cd day2/session1.tex --- a/day2/session1.tex Wed Oct 28 16:05:14 2009 +0530 +++ b/day2/session1.tex Wed Oct 28 16:05:38 2009 +0530 @@ -182,6 +182,7 @@ In [4]: f and t Out[4]: False \end{lstlisting} + \inctime{5} \end{frame} \subsection{Strings} @@ -252,10 +253,8 @@ In [2]: 'x is %s, y is %s' %(x, y) Out[2]: 'x is 1, y is 1.234' \end{lstlisting} -\emphbar{ -\url{http://docs.python.org/library/stdtypes.html}\\ -} -\inctime{10} + \emphbar{\url{http://docs.python.org/library/stdtypes.html}} + \inctime{10} \end{frame} \section{Operators} @@ -338,7 +337,6 @@ In [5]: pos + neg != zer Out[5]: False \end{lstlisting} -\inctime{5} \end{frame} \begin{frame}[fragile] @@ -378,19 +376,6 @@ \inctime{15} \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} - \section{Simple IO} \begin{frame}{Simple IO} \begin{block} @@ -419,7 +404,7 @@ \subsection{Basic Conditional flow} \begin{frame}[fragile] \frametitle{\typ{If...elif...else} example} -\begin{lstlisting} + \begin{lstlisting} x = int(raw_input("Enter an integer:")) if x < 0: print 'Be positive!' @@ -429,7 +414,8 @@ print 'Single' else: print 'More' -\end{lstlisting} + \end{lstlisting} + \inctime{10} \end{frame} \subsection{Basic Looping} @@ -470,7 +456,7 @@ 3 9 4 16 \end{lstlisting} -\inctime{15} +\inctime{5} \end{frame} \subsection{Exercises} @@ -496,10 +482,9 @@ \item It appears that for all starting values there is a cycle of 4, 2, 1 at which the procedure loops. \end{enumerate} Write a program that accepts the starting value and prints out the Collatz sequence. - \end{frame} -\begin{frame}[fragile]{Problem 1.4} +\begin{frame}[fragile]{Problem 1.3} Write a program that prints the following pyramid on the screen. \begin{lstlisting} 1 @@ -510,7 +495,17 @@ The number of lines must be obtained from the user as input.\\ \pause \emphbar{When can your code fail?} -\only<2->{\inctime{20}} +\only<2->{\inctime{10}} +\end{frame} + +\begin{frame}[fragile] + \frametitle{What did we learn?} + \begin{itemize} + \item Basic data types + \item Arithematic, logical and relational operations + \item Conditional structures + \item Loops + \end{itemize} \end{frame} \end{document} diff -r 78ce38a1e383 -r 1575143284cd day2/session2.tex --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/day2/session2.tex Wed Oct 28 16:05:38 2009 +0530 @@ -0,0 +1,522 @@ +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%Tutorial slides on Python. +% +% Author: Prabhu Ramachandran +% 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] + +% Modified from: generic-ornate-15min-45min.de.tex +\mode +{ + \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:\\A formal approach} + +\author[FOSSEE Team] {The FOSSEE Group} + +\institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay} +\date[] {1, November 2009\\Day 2, Session 2} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%\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} + \frametitle{Outline} + \tableofcontents[currentsection,currentsubsection] + \end{frame} +} + +\AtBeginSection[] +{ + \begin{frame} + \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} + +\begin{frame} + \frametitle{Outline} + \tableofcontents + % You might wish to add the option [pausesections] +\end{frame} + +\section{Data structures} +\subsection{Lists} +\begin{frame}[fragile] + \frametitle{Lists} +\begin{block}{We already know that} + \begin{lstlisting} +num = [1, 2, 3, 4, 5, 6, 7, 8] + \end{lstlisting} +\centerline{is a list} +\end{block} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Lists: methods} + \begin{lstlisting} +In []: num.reverse() +In []: num +Out[]: [8, 7, 6, 5, 4, 3, 2, 1] + +In []: num.extend([0, -1, -2]) +In []: num +Out[]: [8, 7, 6, 5, 4, 3, 2, 1, 0, -1] + +In []: num.remove(0) +In []: num +Out[]: [8, 7, 6, 5, 4, 3, 2, 1, -1] + \end{lstlisting} +\end{frame} + +\begin{frame}[fragile] +\frametitle{List containership} +\begin{lstlisting} +In []: a = 8 + +In []: a in num +Out[]: True + +In []: b = 10 +In []: b in num +Out[]: False + +In []: b not in num +Out[]: True +\end{lstlisting} +\end{frame} + +\subsection{Tuples} +\begin{frame}[fragile] +\frametitle{Tuples: Immutable lists} +\begin{lstlisting} +In []: t = (1, 2, 3, 4, 5, 6, 7, 8) +In []: t[0] + t[3] + t[-1] +Out[]: 13 +\end{lstlisting} +\begin{block}{Note:} +\begin{itemize} + \item Tuples are immutable - cannot be changed +\end{itemize} +\end{block} + \inctime{10} +\end{frame} + +\begin{frame} + {A classic problem} + \begin{block} + {Interchange values} + How to interchange values of two variables? + \end{block} + \pause + \begin{block}{Note:} + This Python idiom works for all types of variables.\\ +They need not be of the same type! + \end{block} +\end{frame} + +\subsection{Dictionaries} +\begin{frame}[fragile] + \frametitle{Dictionaries: Recall} + \begin{lstlisting} +In []: player = {'Mat': 134,'Inn': 233, + 'Runs': 10823, 'Avg': 52.53} + +In []: player['Avg'] +Out[]: 52.530000000000001 + \end{lstlisting} + \begin{block}{Note!} + Duplicate keys are not allowed!\\ + Dictionaries are iterable through keys. + \end{block} +\end{frame} + +\begin{frame} {Problem Set 2.1: Problem 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. +\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} +\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{15} +\end{frame} + +\section{Functions} +\begin{frame}[fragile] + \frametitle{Functions} + \begin{itemize} + \item \kwrd{def} - keyword to define a function + \item Arguments are local to a function + \item Docstrings are important! + \item Functions can return multiple values + \end{itemize} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Functions: example} + \begin{lstlisting} +def signum( r ): + """returns 0 if r is zero + -1 if r is negative + +1 if r is positive""" + if r < 0: + return -1 + elif r > 0: + return 1 + else: + return 0 + \end{lstlisting} +\end{frame} + +\begin{frame}[fragile] + {What does this function do?} +\begin{lstlisting} +def what( n ): + i = 1 + while i * i < n: + i += 1 + return i * i == n, i + \end{lstlisting} +\end{frame} + +\subsection{Default arguments} +\begin{frame}[fragile] + \frametitle{Functions: default arguments} + \small + \begin{lstlisting} +def ask_ok(prompt, 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 + print complaint + +ask_ok('?') +ask_ok('?', '[Y/N]') + \end{lstlisting} +\end{frame} + +\subsection{Built-in functions} +\begin{frame} + {Before writing a function} + \begin{itemize} + \item Variety of builtin functions are available + \item \typ{abs, any, all, len, max, min} + \item \typ{pow, range, sum, type} + \item Refer here: + \url{http://docs.python.org/library/functions.html} + \end{itemize} + \inctime{10} +\end{frame} + +\subsection{Exercises} +\begin{frame}{Problem set 3: Problem 3.1} + Write a function to return the gcd of two numbers. +\end{frame} + +\begin{frame}{Problem 3.2} +Write a program to print all primitive pythagorean triads (a, b, c) where a, b are in the range 1---100 \\ +A pythagorean triad $(a,b,c)$ has the property $a^2 + b^2 = c^2$.\\By primitive we mean triads that do not `depend' on others. For example, (4,3,5) is a variant of (3,4,5) and hence is not primitive. And (10,24,26) is easily derived from (5,12,13) and is also not primitive. +\end{frame} + +\begin{frame}{Problem 3.3} + Write a program that generates a list of all four digit numbers that have all their digits even and are perfect squares.\newline\\\emph{For example, the output should include 6400 but not 8100 (one digit is odd) or 4248 (not a perfect square).} +\inctime{15} +\end{frame} + +\section{Modules} +\begin{frame}[fragile] + {Modules} +\begin{lstlisting} +>>> sqrt(2) +Traceback (most recent call last): + File "", line 1, in +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 latter 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} +\inctime{5} +\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}[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{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} + +\section{Objects} +\begin{frame}{Objects in general} + \begin{itemize} + \item What is an Object? (Types and classes) + \item identity + \item type + \item method + \end{itemize} +\end{frame} + +\begin{frame}{Almost everything is an Object!} + \begin{itemize} + \item \typ{list} + \item \typ{tuple} + \item \typ{string} + \item \typ{dictionary} + \item \typ{function} + \item Of course, user defined class objects! + \end{itemize} +\end {frame} + +\begin{frame}{Using Objects} + \begin{itemize} + \item Creating Objects: Initialization + \item Object Manipulation: Object methods and ``.'' operator + \end{itemize} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Objects provide consistency} + \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} +\inctime{10} +\end{frame} + +\begin{frame} + \frametitle{What did we learn?} + \begin{itemize} + \item Lists, Tuples, Dictionaries, Sets: creation and manipulation + \item More about functions + \item Coding style + \item Objects: creation and manipulation + \end{itemize} +\end{frame} + +\end{document}