% Created 2011-07-06 Wed 16:17 \documentclass[presentation]{beamer} \usepackage[latin1]{inputenc} \usepackage[T1]{fontenc} \usepackage{fixltx2e} \usepackage{graphicx} \usepackage{longtable} \usepackage{float} \usepackage{wrapfig} \usepackage{soul} \usepackage{textcomp} \usepackage{marvosym} \usepackage{wasysym} \usepackage{latexsym} \usepackage{amssymb} \usepackage{hyperref} \tolerance=1000 \usepackage[english]{babel} \usepackage{ae,aecompl} \usepackage{mathpazo,courier,euler} \usepackage[scaled=.95]{helvet} \usepackage{listings} \lstset{language=Python, basicstyle=\ttfamily\bfseries, commentstyle=\color{red}\itshape, stringstyle=\color{darkgreen}, showstringspaces=false, keywordstyle=\color{blue}\bfseries} \providecommand{\alert}[1]{\textbf{#1}} \title{} \author{FOSSEE} \date{} \usetheme{Warsaw}\usecolortheme{default}\useoutertheme{infolines}\setbeamercovered{transparent} \begin{document} \begin{frame} \begin{center} \vspace{12pt} \textcolor{blue}{\huge Dictionaries} \end{center} \vspace{18pt} \begin{center} \vspace{10pt} \includegraphics[scale=0.95]{../images/fossee-logo.png}\\ \vspace{5pt} \scriptsize Developed by FOSSEE Team, IIT-Bombay. \\ \scriptsize Funded by National Mission on Education through ICT\\ \scriptsize MHRD,Govt. of India\\ \includegraphics[scale=0.30]{../images/iitb-logo.png}\\ \end{center} \end{frame} \begin{frame} \frametitle{Objectives} \label{sec-2} At the end of this tutorial, you will be able to, \begin{itemize} \item Create dictionaries. \item Add and delete data from dictionaries. \item Retrieve data from dictionaries. \item Check for container-ship of keys. \item Iterate over elements. \end{itemize} \end{frame} \begin{frame} \frametitle{Pre-requisite} \label{sec-3} Spoken tutorial on - \begin{itemize} \item Basic datatypes and operators \end{itemize} \end{frame} \begin{frame} \frametitle{Overview of Dictionaries} \label{sec-4} \begin{itemize} \item A dictionary contains meaning of words \begin{itemize} \item \emph{Word} is the \emph{key} here. \item \emph{Meaning} is the \emph{value} here. \end{itemize} \item A Key-Value pair data structure \begin{itemize} \item Provide key-value mappings \end{itemize} \end{itemize} \end{frame} \begin{frame}[fragile] \frametitle{Accessing Elements} \label{sec-5} \begin{itemize} \item syntax \begin{verbatim} extensions[key] \end{verbatim} \end{itemize} \end{frame} \begin{frame}[fragile] \frametitle{Retrieve keys and values} \label{sec-6} \begin{itemize} \item \verb~.keys()~ method \begin{verbatim} In []: extensions.keys() \end{verbatim} Returns a list of keys in the dictionary. \item \verb~.values()~ method \begin{verbatim} In []: extensions.values() \end{verbatim} Returns the list of values in the dictionary. \end{itemize} \end{frame} \begin{frame} \frametitle{Exercise 1} \label{sec-7} \begin{itemize} \item Print the keys and values in the dictionary one by one. \end{itemize} \end{frame} \begin{frame} \frametitle{Summary} \label{sec-8} In this tutorial, we have learnt to, \begin{itemize} \item Create dictionaries namely -- \begin{itemize} \item empty dictionaries \item dictionaries with data. \end{itemize} \item Access elements in the dictionaries using the keys. \item Add elements to a dictionary by assigning a value to a key. \item Delete elements from a dictionary by using the function ``del''. \item Retrieve the keys and values by using the methods ``.keys()'' and ``.values()'' respectively. \item Iterate over elements of a dictionary using a ``for'' loop. \end{itemize} \end{frame} \begin{frame}[fragile] \frametitle{Evaluation} \label{sec-9} \begin{enumerate} \item Container-ship of values can be checked in a python dictionary \begin{itemize} \item True \item False \vspace{5pt} \end{itemize} \item Consider the python dictionary \begin{verbatim} x = {'a':['a','b','c'], 'b':(1, 2, 3), 1:{1:'one', 2:'two'}, 10:{10:'ten', 11:'eleven'}} \end{verbatim} What will the following code return?\\ \verb~(1, 2, 3) in x.values()~ \vspace{3pt} \begin{itemize} \item True \item False \item Container-ship of values cannot be checked in dictionaries \item The dictionary is invalid \end{itemize} \end{enumerate} \end{frame} \begin{frame} \frametitle{Solutions} \label{sec-10} \begin{enumerate} \item False \vspace{15pt} \item True \end{enumerate} \end{frame} \begin{frame} \begin{block}{} \begin{center} \textcolor{blue}{\Large THANK YOU!} \end{center} \end{block} \begin{block}{} \begin{center} For more Information, visit our website\\ \url{http://fossee.in/} \end{center} \end{block} \end{frame} \end{document}