Conditionals LO - script and questions.

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diff --git a/conditionals/quickref.tex b/conditionals/quickref.tex
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+Creating a linear array:\\
+{\ex \lstinline|    x = linspace(0, 2*pi, 50)|}
+
+Plotting two variables:\\
+{\ex \lstinline|    plot(x, sin(x))|}
+
+Plotting two lists of equal length x, y:\\
+{\ex \lstinline|    plot(x, y)|}
diff --git a/conditionals/script.rst b/conditionals/script.rst
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+.. Objectives
+.. ----------
+
+.. Clearly state the objectives of the LO (along with RBT level)
+
+.. Prerequisites
+.. -------------
+
+..   1. Name of LO-1
+..   2. Name of LO-2
+..   3. Name of LO-3
+     
+.. Author              : Madhu
+   Internal Reviewer   : 
+   External Reviewer   :
+   Checklist OK?       : <put date stamp here, if OK> [2010-10-05]
+
+
+Script
+------
+
+{{{ Show the slide containing the title }}}
+
+Hello friends. Welcome to this spoken tutorial on Getting started with
+strings.
+
+{{{ Show the slide containing the outline }}}
+
+In this tutorial, we will learn the basic conditional constructs
+available in Python. We learn the if/else, if/elif/else and ternary
+conditional constructs available in Python. 
+
+{{{ Shift to terminal and start ipython }}}
+
+To begin with let us start ipython, by typing::
+
+  ipython
+
+on the terminal
+
+Whenever we have two possible states that can occur depending on a
+whether a certain condition we can use if/else construct in
+Python. Say for example we have a variable "a" which stores integers
+and we are required to find out whether the value of the variable "a"
+is an even number or an odd number. To test out conditional statements
+as an example, let us say the value of the variable "a" is 5::
+
+  a = 5
+
+In such a case we can write the if/else block as::
+
+  if a % 2 == 0:
+      print "Even"
+  else:
+      print "Odd"
+
+When the value of the variable "a" is divided by 2 and the remainder
+is 0 i.e. the result of the operation "a modulo 2" is 0 the condition
+"a % 2 == 0" evaluates to True, so the code within the if block gets
+executed. This means that the value of "a" is Even. 
+
+If the operation "a modulo 2" is not 0 the condition "a % 2 == 0"
+evaluates to False and hence the code block within else gets executed
+which means that the value of "a" is Odd. 
+
+Note in such a case only one of the two blocks get executed depending
+on whether the condition is True or False.
+
+There is a very important sytactic element to understand here. All the
+statements which are inside a certain code block are indented by 4
+spaces. The statement which starts a new code block after it, i.e. the
+if statement in this example ends with a colon (:). So the next
+immediate line will be inside the if block and hence indented by 4
+spaces. To come out of the code block we have to come back to the
+previous indentation level as shown in the else line here. Again the
+line following else will be in a new block so else line ends with a
+colon and the following block of code is indented by 4.
+
+As we use if/else statement when we have a condition which can take
+one of the two states, we may have conditions which can take more than
+two states. In such a scenario Python provides if/elif/else
+statements. Let us take an example. We have a variable "a" which holds
+integer values. We need to print "positive" if the value of a is
+positive, "negative" if it is negative and "zero" if the value of the
+variable "a" is 0. Let us use if/elif/else ladder for it. For the
+purposes of testing our code let us assume that the value of a is -3::
+
+  a = -3
+
+  if a > 0:
+      print "positive"
+  elif a < 0:
+      print "negative"
+  else:
+      print "zero"
+
+This if/elif/else ladder is self explanatory. All the syntax and rules
+as said for if/else statements hold. The only addition here is the
+elif statement which can have another condition of its own.
+
+Here, exactly one block of code is executed and that block of code
+corresponds to the condition which first evaluates to True. Even if
+there is a situation where multiple conditions evaluate to True all
+the subsequent conditions other than the first one which evaluates to
+True are neglected. Consequently, the else block gets executed if and
+only if all the conditions evaluate to False.
+
+Also, the else block in both if/else statement and if/elif/else is
+optional. We can have a single if statement or just if/elif statements
+without having else block at all. Also, there can be any number of
+elif's within an if/elif/else ladder. For example
+
+{{{ Show slide for this }}}
+
+  if user == 'admin':
+      # Do admin operations
+  elif user == 'moderator':
+      # Do moderator operations
+  elif user == 'client':
+      # Do customer operations
+
+{{{ end of slide switch to ipython }}}
+
+is completely valid. Note that there are multiple elif blocks and there
+is no else block.
+
+In addition to these conditional statements, Python provides a very
+convenient ternary conditional operator. Let us take the following
+example where we read the marks data from a data file which is
+obtained as a string as we read a file. The marks can be in the range
+of 0 to 100 or 'AA' if the student is absent. In such a case to obtain
+the marks as an integer we can use the ternary conditional
+operator. Let us say the string score is stored in score_str
+variable::
+
+  score_str = 'AA'
+
+Now let us use the ternary conditional operator::
+
+  score = int(score_str) if score_str != 'AA' else 0
+
+This is just the if/else statement block which written in a more
+convenient form and is very helpful when we have only one statement
+for each block. This conditional statement effectively means as we
+would have exactly specified in the English language which will be
+like score is integer of score_str is score_str is not 'AA' otherwise
+it is 0. This means that we make the scores of the students who were
+absent for the exam 0.
+
+Moving on, there are certain situations where we will have to no
+operations or statements within the block of code. For example, we
+have a code where we are waiting for the keyboard input. If the user
+enters "s" as the input we would perform some operation nothing
+otherwise. In such cases "pass" statement comes very handy::
+
+  a = raw_input("Enter 'c' to calculate and exit, 'd' to display the existing
+  results exit and 'x' to exit and any other key to continue: ")
+
+  if a == 'c':
+     # Calculate the marks and exit
+  elif a == 'd':
+     # Display the results and exit
+  elif a == 'x':
+     # Exit the program
+  else:
+     pass
+
+In this case "pass" statement acts as a place holder for the block of
+code. It is equivalent to a null operation. It literally does
+nothing. So "pass" statement can be used as a null operation
+statement, or it can used as a place holder when the actual code
+implementation for a particular block of code is not known yet but has
+to be filled up later.
+
+{{{ Show summary slide }}}
+
+This brings us to the end of the tutorial session on conditional
+statements in Python. In this tutorial session we learnt
+
+  * What are conditional statements
+  * if/else statement
+  * if/elif/else statement
+  * Ternary conditional statement - C if X else Y
+  * and the "pass" statement
+
+{{{ Show the "sponsored by FOSSEE" slide }}}
+
+This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India
+
+Hope you have enjoyed and found it useful.
+Thank you!
+ 
diff --git a/conditionals/slides.org b/conditionals/slides.org
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+#+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
+
+
diff --git a/conditionals/slides.tex b/conditionals/slides.tex
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+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%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}
+\usepackage[latin1]{inputenc}
+%\usepackage{times}
+\usepackage[T1]{fontenc}
+
+\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]{\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}
+\date{}
+
+% DOCUMENT STARTS
+\begin{document}
+
+\begin{frame}
+  \maketitle
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Outline}
+  \begin{itemize}
+    \item 
+  \end{itemize}
+\end{frame}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%              All other slides here.                  %%
+%% The same slides will be used in a classroom setting. %% 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\begin{frame}[fragile]
+  \frametitle{Summary}
+  \begin{itemize}
+    \item 
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Thank you!}  
+  \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{frame}
+
+\end{document}