Split session 1 into two parts.

2 files changed, 474 insertions, 279 deletions

diff --git a/scipy/basic/session1.tex b/scipy/basic/session1a.tex
index 729f50c..ded2a91 100644
--- a/scipy/basic/session1.tex
+++ b/scipy/basic/session1a.tex
@@ -659,285 +659,6 @@ In []: plot??
 \end{center}
 \end{frame}
 
-\begin{frame}[fragile]
-\frametitle{Review Problem \ldots}
-\alert{Plotting \ldots}
-\begin{lstlisting}
-In []: x = linspace(-5*pi, 5*pi, 500)
-In []: plot(x, x, 'b')
-In []: plot(x, -x, 'b')
-In []: plot(x, sin(x), 'g', linewidth=2)
-In []: plot(x, x*sin(x), 'r',
-            linewidth=3)
-\end{lstlisting}
-$\vdots$
-\end{frame}
-
-\begin{frame}[fragile]
-\frametitle{Review Problem \ldots}
-\alert{Legend \& Annotation\ldots}
-\begin{lstlisting}
-In []: legend(['x', '-x', 'sin(x)',
-               'xsin(x)'])
-In []: annotate('origin', xy = (0, 0))
-\end{lstlisting}
-\alert{Setting Axes limits\ldots}
-\begin{lstlisting}
-In []: xlim(-5*pi, 5*pi)
-In []: ylim(-5*pi, 5*pi)
-\end{lstlisting}
-\inctime{5}
-\end{frame}
-
-\section{Scripts -- Saving \& Running}
-\begin{frame}[fragile]
-\frametitle{Command History}
-Use the \typ{\%hist} \alert{magic} command of IPython
-\typ{In []: \%hist}\\
-This displays the ``Command History''
-\begin{block}{Careful about errors!}
-  \kwrd{\%hist} will contain the errors as well.\\
-\end{block}
-\pause
-\begin{block}{Magic Commands?}
-  Magic commands are commands provided by IPython to make our life easier.
-\end{block}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Saving commands into script}
-Use the \typ{\%save} \alert{magic} command of IPython
-\begin{block}{}
-\typ{\%save script_name line_numbers}
-\end{block}
-Line numbers specified individually separated by spaces or as a range separated by a dash.\\
-\begin{block}{}
-\typ{\%save four_plot.py} \alert{\typ{  16 18-27}} \\
-\end{block}
-Saves from history the commands entered on line numbers \alert{16, 18, 19, 20, \ldots 27}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Saving commands into a script}
-  \begin{itemize}
-  \item Save lines relevant for the review problem
-  \item Hint: example\\ \typ{\%save four_plot.py 16 18-27}
-  \item Choose the lines carefully
-  \item Edit \typ{four_plot.py} on Canopy
-  \item Make sure all the lines are correct
-  \item Save the script
-  \end{itemize}
-\inctime{5}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Creating scripts: alternative}
-  \begin{itemize}
-  \item Create a new file on Canopy
-  \item Copy commands for assignment with your mouse
-  \item Save the script to \typ{four_plot.py}
-  \end{itemize}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Where is the script saved?}
-  \begin{itemize}
-  \item \typ{\%save} saves into the current directory
-    \vspace*{0.5in}
-  \item Use \typ{\%pwd} to print the current directory
-  \item Use \typ{\%cd} to change the directory
-  \end{itemize}
-\end{frame}
-
-
-\begin{frame}[fragile]
-\frametitle{Python Scripts\ldots}
-Now, \typ{four_plot.py} is called a Python Script.
- \begin{itemize}
- \item run the script in IPython using \typ{\%run four_plot.py}\\
- \end{itemize}
-\pause
-\alert{\typ{NameError: name 'linspace' is not defined}}
-\begin{block}{}
-To avoid this, run using \alert{\typ{\%run -i four_plot.py}}\\
-\end{block}
-\pause
-Where is the plot?
-\begin{lstlisting}
-In []: show()
-\end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Exercise}
-  \begin{itemize}
-  \item Add the \typ{show()} command to \typ{four_plot.py}
-  \item Save the file
-  \item Test that it works
-  \end{itemize}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Result graph}
-  \begin{center}
-    \includegraphics[height=3in, interpolate=true]{data/four_plot}
-  \end{center}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Running with Python}
-  \begin{itemize}
-  \item Start a new Canopy terminal
-  \item Change directory to where you saved \typ{four_plot.py}
-  \item Run the script as:
-  \end{itemize}
-\begin{lstlisting}
- $ python four_plot.py
-\end{lstlisting}
-  \pause
-  Do you see:
-  \begin{small}
-\begin{lstlisting}
-NameError: name 'linspace' is not defined
-\end{lstlisting}
-  \end{small}
-\inctime{5}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Imports}
-  \begin{itemize}
-  \item \typ{ipython --pylab} does magic
-  \item Import libraries using \typ{import}
-  \end{itemize}
-\begin{lstlisting}
-In []: from pylab import linspace
-\end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Exercise}
-  \begin{itemize}
-  \item Add \typ{from pylab import linspace} to top of \typ{four_plot.py}
-  \item Test that it works
-  \end{itemize}
-\begin{lstlisting}
-# four_plot.py
-from pylab import linspace # <-- added
-x = linspace(-5*pi, 5*pi, 500)
-plot(x, x, 'b')
-...
-\end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Try again}
-  \begin{itemize}
-  \item On Canopy terminal
-  \item Run the script as:
-  \end{itemize}
-\begin{lstlisting}
- $ python four_plot.py
-\end{lstlisting}
-  \pause
-  \vspace*{0.15in}
-  Do you see:
-  \begin{small}
-\begin{lstlisting}
-NameError: name 'plot' is not defined
-\end{lstlisting}
-  \end{small}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Exercise}
-  \begin{itemize}
-  \item Change line 1 to \typ{from pylab import *}
-  \item Test that it works
-  \end{itemize}
-\begin{lstlisting}
-# four_plot.py
-from pylab import * # <-- added
-x = linspace(-5*pi, 5*pi, 500)
-plot(x, x, 'b')
-...
-\end{lstlisting}
-\inctime{5}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Solution}
-  \small
-\begin{lstlisting}
-from pylab import *
-x = linspace(-5*pi, 5*pi, 500)
-plot(x, x, 'b')
-plot(x, -x, 'b')
-plot(x, sin(x), 'g', linewidth=2)
-plot(x, x*sin(x), 'r', linewidth=3)
-legend(['x', '-x', 'sin(x)',
-               'xsin(x)'])
-annotate('origin', xy = (0, 0))
-xlim(-5*pi, 5*pi)
-ylim(-5*pi, 5*pi)
-show()
-\end{lstlisting}
-\end{frame}
-
-
-
-\begin{frame}[fragile]
-  \frametitle{What did we learn?}
-  \begin{itemize}
-    \item Starting up IPython
-    \item Creating simple plots
-    \item Annotating: labels, legends, annotation
-    \item Changing the looks: color, linewidth
-    \item Accessing history, documentation
-    \item \kwrd{\%hist} - History of commands
-    \item Creating a Python script with \typ{\%save}
-    \item Running a script using \kwrd{\%run -i}
-    \item Importing functionality
-    \item Running a script with\ \typ{python script.py}
-  \end{itemize}
-\end{frame}
-
-\begin{frame}
-  \frametitle{Using Canopy}
-  \begin{itemize}
-  \item Much easier
-  \item Write code in the editor
-  \item Embedded IPython
-  \item Save (Ctrl-S or Cmd-S)
-  \item Run selection: Ctrl-Shift-R (Cmd-Shift-R on OS X)
-  \item Run code: Ctrl-R (Cmd-R on OS X)
-  \item Change directory with menu (\typ{\%cd})
-  \end{itemize}
-  \inctime{5}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Note on script file names}
-  \begin{itemize}
-  \item Should start with a letter
-  \item Can use \typ{_} (underscore) and numbers
-  \item No \typ{.} allowed
-  \item No spaces or special characters
-  \end{itemize}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Test}
-  \begin{itemize}
-  \item \typ{1_script.py}
-  \item \typ{script_1.py}
-  \item \typ{one11.py}
-  \item \typ{one script.py}
-  \item \typ{one,script;xxx.py}
-  \item \typ{one.two.py}
-  \end{itemize}
-\end{frame}
-
 \end{document}
 
 %% Questions for Quiz %%
diff --git a/scipy/basic/session1b.tex b/scipy/basic/session1b.tex
new file mode 100644
index 0000000..87b2a8a
--- /dev/null
+++ b/scipy/basic/session1b.tex
@@ -0,0 +1,474 @@
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%Tutorial slides on Python.
+%
+% Author: FOSSEE
+% Copyright (c) 2009-2016, FOSSEE, IIT Bombay
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\documentclass[14pt,compress]{beamer}
+
+% 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}
+
+% 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]{\lstinline{#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[Interactive Plotting]{Introductory Scientific Computing with
+Python}
+\subtitle{Saving scripts}
+
+\author[FOSSEE] {FOSSEE}
+
+\institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
+\date[] {Mumbai, India
+}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%\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}<beamer>
+    \frametitle{Outline}
+    \tableofcontents[currentsection,currentsubsection]
+  \end{frame}
+}
+
+\AtBeginSection[]
+{
+  \begin{frame}<beamer>
+    \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}
+  \maketitle
+\end{frame}
+
+%% \begin{frame}
+%%   \frametitle{Outline}
+%%   \tableofcontents
+%%   % You might wish to add the option [pausesections]
+%% \end{frame}
+
+\section{Exercise}
+
+\begin{frame}[plain,fragile]
+\frametitle{Review Problem}
+\begin{enumerate}
+\item Plot $x, -x, \sin(x), x \sin(x)$ in range $-5\pi$ to $5\pi$
+\item Add a legend
+\item Annotate the origin
+\item Set axes limits to the range of x
+\end{enumerate}
+\vspace*{-0.15in}
+\begin{center}
+  \includegraphics[height=2.6in, interpolate=true]{data/four_plot}
+\end{center}
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{Review Problem \ldots}
+\alert{Plotting \ldots}
+\begin{lstlisting}
+In []: x = linspace(-5*pi, 5*pi, 500)
+In []: plot(x, x, 'b')
+In []: plot(x, -x, 'b')
+In []: plot(x, sin(x), 'g', linewidth=2)
+In []: plot(x, x*sin(x), 'r',
+            linewidth=3)
+\end{lstlisting}
+$\vdots$
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{Review Problem \ldots}
+\alert{Legend \& Annotation\ldots}
+\begin{lstlisting}
+In []: legend(['x', '-x', 'sin(x)',
+               'xsin(x)'])
+In []: annotate('origin', xy = (0, 0))
+\end{lstlisting}
+\alert{Setting Axes limits\ldots}
+\begin{lstlisting}
+In []: xlim(-5*pi, 5*pi)
+In []: ylim(-5*pi, 5*pi)
+\end{lstlisting}
+\inctime{5}
+\end{frame}
+
+\section{Scripts -- Saving \& Running}
+\begin{frame}[fragile]
+\frametitle{Command History}
+Use the \typ{\%hist} \alert{magic} command of IPython
+\typ{In []: \%hist}\\
+This displays the ``Command History''
+\begin{block}{Careful about errors!}
+  \kwrd{\%hist} will contain the errors as well.\\
+\end{block}
+\pause
+\begin{block}{Magic Commands?}
+  Magic commands are commands provided by IPython to make our life easier.
+\end{block}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Saving commands into script}
+Use the \typ{\%save} \alert{magic} command of IPython
+\begin{block}{}
+\typ{\%save script_name line_numbers}
+\end{block}
+Line numbers specified individually separated by spaces or as a range separated by a dash.\\
+\begin{block}{}
+\typ{\%save four_plot.py} \alert{\typ{  16 18-27}} \\
+\end{block}
+Saves from history the commands entered on line numbers \alert{16, 18, 19, 20, \ldots 27}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Saving commands into a script}
+  \begin{itemize}
+  \item Save lines relevant for the review problem
+  \item Hint: example\\ \typ{\%save four_plot.py 16 18-27}
+  \item Choose the lines carefully
+  \item Edit \typ{four_plot.py} on Canopy
+  \item Make sure all the lines are correct
+  \item Save the script
+  \end{itemize}
+\inctime{5}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Creating scripts: alternative}
+  \begin{itemize}
+  \item Create a new file on Canopy
+  \item Copy commands for assignment with your mouse
+  \item Save the script to \typ{four_plot.py}
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Where is the script saved?}
+  \begin{itemize}
+  \item \typ{\%save} saves into the current directory
+    \vspace*{0.5in}
+  \item Use \typ{\%pwd} to print the current directory
+  \item Use \typ{\%cd} to change the directory
+
+    \vspace*{0.5in}
+  \item Question: how do you find out more about \typ{\%cd}?
+  \end{itemize}
+\end{frame}
+
+
+\begin{frame}[fragile]
+\frametitle{Python Scripts\ldots}
+Now, \typ{four_plot.py} is called a Python Script.
+ \begin{itemize}
+ \item run the script in IPython using \typ{\%run four_plot.py}\\
+ \end{itemize}
+\pause
+\alert{\typ{NameError: name 'linspace' is not defined}}
+\begin{block}{}
+To avoid this, run using \alert{\typ{\%run -i four_plot.py}}\\
+\end{block}
+\pause
+Where is the plot?
+\begin{lstlisting}
+In []: show()
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Exercise}
+  \begin{itemize}
+  \item Add the \typ{show()} command to \typ{four_plot.py}
+  \item Save the file
+  \item Test that it works
+  \end{itemize}
+  \inctime{5}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Result graph}
+  \begin{center}
+    \includegraphics[height=3in, interpolate=true]{data/four_plot}
+  \end{center}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Running with Python}
+  \begin{itemize}
+  \item Start a new Canopy terminal
+  \item Change directory to where you saved \typ{four_plot.py}
+  \item Run the script as:
+  \end{itemize}
+\begin{lstlisting}
+ $ python four_plot.py
+\end{lstlisting}
+  \pause
+  Do you see:
+  \begin{small}
+\begin{lstlisting}
+NameError: name 'linspace' is not defined
+\end{lstlisting}
+  \end{small}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Imports}
+  \begin{itemize}
+  \item \typ{ipython --pylab} does magic
+  \item Import libraries using \typ{import}
+  \end{itemize}
+\begin{lstlisting}
+In []: from pylab import linspace
+\end{lstlisting}
+\inctime{5}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Exercise}
+  \begin{itemize}
+  \item Add \typ{from pylab import linspace} to top of \typ{four_plot.py}
+  \item Test that it works
+  \end{itemize}
+\begin{lstlisting}
+# four_plot.py
+from pylab import linspace # <-- added
+x = linspace(-5*pi, 5*pi, 500)
+plot(x, x, 'b')
+...
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Try again}
+  \begin{itemize}
+  \item On Canopy terminal
+  \item Run the script as:
+  \end{itemize}
+\begin{lstlisting}
+ $ python four_plot.py
+\end{lstlisting}
+  \pause
+  \vspace*{0.15in}
+  Do you see:
+  \begin{small}
+\begin{lstlisting}
+NameError: name 'plot' is not defined
+\end{lstlisting}
+  \end{small}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Exercise}
+  \begin{itemize}
+  \item Change line 1 to \typ{from pylab import *}
+  \item Test that it works
+  \end{itemize}
+\begin{lstlisting}
+# four_plot.py
+from pylab import * # <-- added
+x = linspace(-5*pi, 5*pi, 500)
+plot(x, x, 'b')
+...
+\end{lstlisting}
+\inctime{5}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Solution}
+  \small
+\begin{lstlisting}
+from pylab import *
+x = linspace(-5*pi, 5*pi, 500)
+plot(x, x, 'b')
+plot(x, -x, 'b')
+plot(x, sin(x), 'g', linewidth=2)
+plot(x, x*sin(x), 'r', linewidth=3)
+legend(['x', '-x', 'sin(x)', 'xsin(x)'])
+annotate('origin', xy = (0, 0))
+xlim(-5*pi, 5*pi)
+ylim(-5*pi, 5*pi)
+show()
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Note on script file names}
+  \begin{itemize}
+  \item Should start with a letter
+  \item Can use \typ{_} (underscore) and numbers
+  \item No \typ{.} allowed
+  \item No spaces or special characters
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Test}
+  \begin{itemize}
+  \item \typ{1_script.py}
+  \item \typ{script_1.py}
+  \item \typ{one11.py}
+  \item \typ{one script.py}
+  \item \typ{one,script;xxx.py}
+  \item \typ{one.two.py}
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Using Canopy}
+  \begin{itemize}
+  \item Much easier
+  \item Write code in the editor
+  \item Embedded IPython
+  \item Save (Ctrl-S or Cmd-S)
+  \item Run selection: Ctrl-Shift-R (Cmd-Shift-R on OS X)
+  \item Run code: Ctrl-R (Cmd-R on OS X)
+  \item Change directory with menu (\typ{\%cd})
+  \end{itemize}
+  \inctime{5}
+\end{frame}
+
+
+\begin{frame}[fragile]
+  \frametitle{What did we learn?}
+  \begin{itemize}
+    \item Starting up IPython
+    \item Creating simple plots
+    \item Annotating: labels, legends, annotation
+    \item Changing the looks: color, linewidth
+    \item Accessing history, documentation
+    \item \kwrd{\%hist} - History of commands
+    \item Creating a Python script with \typ{\%save}
+    \item Running a script using \kwrd{\%run -i}
+    \item Importing functionality
+    \item Running a script with\ \typ{python script.py}
+  \end{itemize}
+\end{frame}
+
+
+\end{document}
+
+%% Questions for Quiz %%
+%% ------------------ %%
+
+\begin{frame}[fragile]
+\frametitle{\incqno }
+Draw (roughly) the plot obtained by the following:
+\begin{lstlisting}
+In []: x = linspace(0, pi, 3)
+In []: plot(x, sin(x))
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{\incqno }
+Describe the plot produced by the following:
+\begin{lstlisting}
+In []: x = linspace(0, 2*pi, 50)
+In []: plot(x, cos(x), 'go')
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}
+\frametitle{\incqno }
+How will you plot the previous graph with line width set to 3?  How will
+you set the $x$ and $y$ labels of the plot?
+\end{frame}
+
+\begin{frame}
+\frametitle{\incqno }
+How will you set the x and y axis limits so that the region of interest
+is in the rectangle $(0, -1.5)$ (left bottom coordinate) and $(2\pi,
+1.5)$ (right top coordinate)?
+\end{frame}
+
+\begin{frame}
+\frametitle{\incqno }
+What ipython magic command do you use to obtain the lines of code you have already typed in the interpreter? What command do you use to save them?
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{\incqno }
+The following code snippet has an error/bug:
+\begin{lstlisting}
+In []: y = linspace(0, 2*pi, 50)
+In []: plot(y, sin(y))
+In []: clf()
+In []: plot(y, cos(y))
+In []: legend(['sin(y)', 'cos(y)'])
+\end{lstlisting}
+What is the error? How do you fix it?
+\end{frame}