--- a/accessing-pieces-arrays/script.rst	Sun Oct 10 13:46:09 2010 +0530
+++ b/accessing-pieces-arrays/script.rst	Mon Oct 11 00:52:58 2010 +0530
@@ -298,8 +298,7 @@
 
 Following is an exercise that you must do. 
 
-%%5%% Pause the video here, and obtain the square in the center
-of the image. 
+%%5%% Obtain the square in the center of the image.
 
 Following is an exercise that you must do. 
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/accessing-pieces-arrays/slides.org	Mon Oct 11 00:52:58 2010 +0530
@@ -0,0 +1,123 @@
+#+LaTeX_CLASS: beamer
+#+LaTeX_CLASS_OPTIONS: [presentation]
+#+BEAMER_FRAME_LEVEL: 1
+
+#+BEAMER_HEADER_EXTRA: \usetheme{Warsaw}\usecolortheme{default}\useoutertheme{infolines}\setbeamercovered{transparent}
+#+COLUMNS: %45ITEM %10BEAMER_env(Env) %10BEAMER_envargs(Env Args) %4BEAMER_col(Col) %8BEAMER_extra(Extra)
+#+PROPERTY: BEAMER_col_ALL 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 :ETC
+
+#+LaTeX_CLASS: beamer
+#+LaTeX_CLASS_OPTIONS: [presentation]
+
+#+LaTeX_HEADER: \usepackage[english]{babel} \usepackage{ae,aecompl}
+#+LaTeX_HEADER: \usepackage{mathpazo,courier,euler} \usepackage[scaled=.95]{helvet}
+
+#+LaTeX_HEADER: \usepackage{listings}
+
+#+LaTeX_HEADER:\lstset{language=Python, basicstyle=\ttfamily\bfseries,
+#+LaTeX_HEADER:  commentstyle=\color{red}\itshape, stringstyle=\color{darkgreen},
+#+LaTeX_HEADER:  showstringspaces=false, keywordstyle=\color{blue}\bfseries}
+
+#+TITLE:    Accessing parts of arrays
+#+AUTHOR:    FOSSEE
+#+EMAIL:     
+#+DATE:    
+
+#+DESCRIPTION: 
+#+KEYWORDS: 
+#+LANGUAGE:  en
+#+OPTIONS:   H:3 num:nil toc:nil \n:nil @:t ::t |:t ^:t -:t f:t *:t <:t
+#+OPTIONS:   TeX:t LaTeX:nil skip:nil d:nil todo:nil pri:nil tags:not-in-toc
+
+* Outline
+  - Manipulating one and multi dimensional arrays
+  - Access and change individual elements 
+  - Access and change rows and columns 
+  - Slicing and striding on arrays to access chunks 
+  - Read images into arrays and manipulations
+* Sample Arrays
+  #+begin_src python
+    In []: A = array([12, 23, 34, 45, 56])
+    
+    In []: C = array([[11, 12, 13, 14, 15],
+                      [21, 22, 23, 24, 25],
+                      [31, 32, 33, 34, 35],
+                      [41, 42, 43, 44, 45],
+                      [51, 52, 53, 54, 55]])
+    
+  #+end_src
+* Question 1
+  Change the last column of ~C~ to zeroes. 
+* Solution 1
+  #+begin_src python
+    In []:  C[:, -1] = 0
+  #+end_src
+* Question 2
+  Change ~A~ to ~[11, 12, 13, 14, 15]~. 
+* Solution 2
+  #+begin_src python
+    In []:  A[:] = [11, 12, 13, 14, 15]
+  #+end_src
+* squares.png
+  #+begin_latex
+    \begin{center}
+      \includegraphics[scale=0.6]{squares}    
+    \end{center}
+  #+end_latex
+* Question 3
+  - obtain ~[22, 23]~ from ~C~. 
+  - obtain ~[11, 21, 31, 41]~ from ~C~. 
+  - obtain ~[21, 31, 41, 0]~.   
+* Solution 3
+  #+begin_src python
+    In []:  C[1, 1:3]
+    In []:  C[0:4, 0]
+    In []:  C[1:5, 0]
+  #+end_src
+* Question 4
+  Obtain ~[[23, 24], [33, -34]]~ from ~C~
+* Solution 4
+  #+begin_src python
+    In []:  C[1:3, 2:4]
+  #+end_src
+* Question 5
+  Obtain the square in the center of the image
+* Solution 5
+  #+begin_src python
+    In []: imshow(I[75:225, 75:225])
+  #+end_src
+* Question 6
+  Obtain the following
+  #+begin_src python
+    [[12, 0], [42, 0]]
+    [[12, 13, 14], [0, 0, 0]]
+  #+end_src
+
+* Solution 6
+  #+begin_src python
+    In []: C[::3, 1::3]
+    In []: C[::4, 1:4]
+  #+end_src
+* Summary
+  You should now be able to --
+  - Manipulate 1D \& Multi dimensional arrays
+      - Access and change individual elements 
+      - Access and change rows and columns 
+      - Slice and stride on arrays
+  - Read images into arrays and manipulate them.
+* Thank you!
+#+begin_latex
+  \begin{block}{}
+  \begin{center}
+  This spoken tutorial has been produced by the
+  \textcolor{blue}{FOSSEE} team, which is funded by the 
+  \end{center}
+  \begin{center}
+    \textcolor{blue}{National Mission on Education through \\
+      Information \& Communication Technology \\ 
+      MHRD, Govt. of India}.
+  \end{center}  
+  \end{block}
+#+end_latex
+
+

--- a/accessing-pieces-arrays/slides.tex	Sun Oct 10 13:46:09 2010 +0530
+++ b/accessing-pieces-arrays/slides.tex	Mon Oct 11 00:52:58 2010 +0530
@@ -1,95 +1,203 @@
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%Tutorial slides on Python.
-%
-% Author: FOSSEE 
-% Copyright (c) 2009, FOSSEE, IIT Bombay
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\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{infolines}
-  \setbeamercovered{transparent}
-}
-
-\usepackage[english]{babel}
+% Created 2010-10-10 Sun 18:48
+\documentclass[presentation]{beamer}
 \usepackage[latin1]{inputenc}
-%\usepackage{times}
 \usepackage[T1]{fontenc}
-
-\usepackage{ae,aecompl}
-\usepackage{mathpazo,courier,euler}
-\usepackage[scaled=.95]{helvet}
+\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}}
 
-\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]{\lstinline{#1}}
-
-\newcommand{\kwrd}[1]{ \texttt{\textbf{\color{blue}{#1}}}  }
-
-% Title page
-\title{Your Title Here}
-
-\author[FOSSEE] {FOSSEE}
-
-\institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
+\title{Accessing parts of arrays}
+\author{FOSSEE}
 \date{}
 
-% DOCUMENT STARTS
+\usetheme{Warsaw}\usecolortheme{default}\useoutertheme{infolines}\setbeamercovered{transparent}
 \begin{document}
 
+\maketitle
+
+
+
+
+
+
+
+
+
 \begin{frame}
-  \maketitle
+\frametitle{Outline}
+\label{sec-1}
+
+\begin{itemize}
+\item Manipulating one and multi dimensional arrays
+\item Access and change individual elements
+\item Access and change rows and columns
+\item Slicing and striding on arrays to access chunks
+\item Read images into arrays and manipulations
+\end{itemize}
 \end{frame}
+\begin{frame}[fragile]
+\frametitle{Sample Arrays}
+\label{sec-2}
 
+\lstset{language=Python}
+\begin{lstlisting}
+In []: A = array([12, 23, 34, 45, 56])
+
+In []: C = array([[11, 12, 13, 14, 15],
+                  [21, 22, 23, 24, 25],
+                  [31, 32, 33, 34, 35],
+                  [41, 42, 43, 44, 45],
+                  [51, 52, 53, 54, 55]])
+\end{lstlisting}
+\end{frame}
+\begin{frame}
+\frametitle{Question 1}
+\label{sec-3}
+
+  Change the last column of \texttt{C} to zeroes. 
+\end{frame}
 \begin{frame}[fragile]
-  \frametitle{Outline}
-  \begin{itemize}
-    \item 
-  \end{itemize}
+\frametitle{Solution 1}
+\label{sec-4}
+
+\lstset{language=Python}
+\begin{lstlisting}
+In []:  C[:, -1] = 0
+\end{lstlisting}
+\end{frame}
+\begin{frame}
+\frametitle{Question 2}
+\label{sec-5}
+
+  Change \texttt{A} to \texttt{[11, 12, 13, 14, 15]}. 
 \end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 2}
+\label{sec-6}
+
+\lstset{language=Python}
+\begin{lstlisting}
+In []:  A[:] = [11, 12, 13, 14, 15]
+\end{lstlisting}
+\end{frame}
+\begin{frame}
+\frametitle{squares.png}
+\label{sec-7}
+
+    \begin{center}
+      \includegraphics[scale=0.6]{squares}    
+    \end{center}
+\end{frame}
+\begin{frame}
+\frametitle{Question 3}
+\label{sec-8}
+
+\begin{itemize}
+\item obtain \texttt{[22, 23]} from \texttt{C}.
+\item obtain \texttt{[11, 21, 31, 41]} from \texttt{C}.
+\item obtain \texttt{[21, 31, 41, 0]}.
+\end{itemize}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 3}
+\label{sec-9}
 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%%              All other slides here.                  %%
-%% The same slides will be used in a classroom setting. %% 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+\lstset{language=Python}
+\begin{lstlisting}
+In []:  C[1, 1:3]
+In []:  C[0:4, 0]
+In []:  C[1:5, 0]
+\end{lstlisting}
+\end{frame}
+\begin{frame}
+\frametitle{Question 4}
+\label{sec-10}
+
+  Obtain \texttt{[[23, 24], [33, -34]]} from \texttt{C}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 4}
+\label{sec-11}
 
+\lstset{language=Python}
+\begin{lstlisting}
+In []:  C[1:3, 2:4]
+\end{lstlisting}
+\end{frame}
+\begin{frame}
+\frametitle{Question 5}
+\label{sec-12}
+
+  Obtain the square in the center of the image
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 5}
+\label{sec-13}
+
+\lstset{language=Python}
+\begin{lstlisting}
+In []: imshow(I[75:225, 75:225])
+\end{lstlisting}
+\end{frame}
 \begin{frame}[fragile]
-  \frametitle{Summary}
-  \begin{itemize}
-    \item 
-  \end{itemize}
+\frametitle{Question 6}
+\label{sec-14}
+
+  Obtain the following
+\lstset{language=Python}
+\begin{lstlisting}
+[[12, 0], [42, 0]]
+[[12, 13, 14], [0, 0, 0]]
+\end{lstlisting}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 6}
+\label{sec-15}
+
+\lstset{language=Python}
+\begin{lstlisting}
+In []: C[::3, 1::3]
+In []: C[::4, 1:4]
+\end{lstlisting}
 \end{frame}
-
 \begin{frame}
-  \frametitle{Thank you!}  
+\frametitle{Summary}
+\label{sec-16}
+
+  You should now be able to --
+\begin{itemize}
+\item Manipulate 1D \& Multi dimensional arrays
+
+\begin{itemize}
+\item Access and change individual elements
+\item Access and change rows and columns
+\item Slice and stride on arrays
+\end{itemize}
+
+\item Read images into arrays and manipulate them.
+\end{itemize}
+\end{frame}
+\begin{frame}
+\frametitle{Thank you!}
+\label{sec-17}
+
   \begin{block}{}
   \begin{center}
   This spoken tutorial has been produced by the