Branches merged.
authorSantosh G. Vattam <vattam.santosh@gmail.com>
Fri, 06 Nov 2009 18:40:13 +0530
changeset 292 2622aebff64a
parent 291 ec70a2048871 (current diff)
parent 289 884d42eff66d (diff)
child 293 f7d7b5565232
Branches merged.
Binary file day1/data/smoothing.gif has changed
--- a/day1/session3.tex	Fri Nov 06 18:39:56 2009 +0530
+++ b/day1/session3.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -78,6 +78,7 @@
 \author[FOSSEE] {FOSSEE}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
+
 \date[] {7 November, 2009\\Day 1, Session 3}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
@@ -126,67 +127,88 @@
 %%   % You might wish to add the option [pausesections]
 %% \end{frame}
 
+\section{Computing mean}
+\begin{frame}
+  \frametitle{Value of acceleration due to gravity?}
+  \begin{itemize}
+    \item We already have pendulum.txt
+    \item We know that $ T = 2\pi \sqrt{\frac{L}{g}} $
+    \item So $ g = \frac{4 \pi^2 L}{T^2}  $
+    \item Calculate ``g'' - acceleration due to gravity for each pair of L and T
+    \item Hence calculate mean ``g''
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Acceleration due to gravity - ``g''\ldots}
+  \begin{lstlisting}
+In []: G = []
+In []: for line in open('pendulum.txt'):
+  ....     points = line.split()
+  ....     l = float(points[0])
+  ....     t = float(points[1])
+  ....     g = 4 * pi * pi * l / t * t
+  ....     G.append(g)
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Computing mean ``g''}
+  \begin{block}{Exercise}
+    Obtain the mean of ``g''
+  \end{block}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Mean ``g''}
+  \begin{lstlisting}
+total = 0
+for g in G:
+    total += g
+
+mean_g = total / len(g)
+print "Mean: ", mean_g
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Mean ``g''}
+  \begin{lstlisting}
+mean_g = sum(G) / len(G)
+print "Mean: ", mean_g
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Mean ``g''}
+  \begin{lstlisting}
+mean_g = mean(G)
+print "Mean: ", mean_g
+  \end{lstlisting}
+  \inctime{10}
+\end{frame}
+
 \section{Processing voluminous data}
 \begin{frame}
   \frametitle{More on data processing}
   \begin{block}{}
-    We have a huge--1m records--data file.\\How do we do \emph{efficient} statistical computations, that is find mean, median, mode, standard deveiation etc; draw pie charts?
+    We have a huge data file--180,000 records.\\How do we do \emph{efficient} statistical computations, i.e. find mean, median, standard deviation etc; draw pie charts?
   \end{block}
 \end{frame}
 
-
-\begin{frame}
-  \frametitle{Statistical Analysis: Problem statement}
-  Read the data supplied in \emph{sslc1.txt} and carry out the following:
-  \begin{enumerate}
-    \item Draw a pie chart representing the proportion of students who scored more than 90\% in each region in Science.
-    \item Draw a pie chart representing the proportion of students who scored more than 90\% in each subject across regions.
-    \item Print mean, median, mode and standard deviation of math scores for all regions combined.
-  \end{enumerate}
-\end{frame}
-
-\begin{frame}
-  \frametitle{Problem statement: explanation}
-    \emphbar{Draw a pie chart representing the proportion of students who scored more than 90\% in each region in Science.}
-    \begin{enumerate}
-      \item Complete(100\%) data - Number of students who scored more than 90\% in Science
-      \item Each slice - Number of students who scored more than 90\% in Science in one region
-    \end{enumerate}
-\end{frame}
-
 \begin{frame}
-  \frametitle{Problem statement: explanation}
-    \emphbar{Draw a pie chart representing the proportion of students who scored more than 90\% in each subject across regions.}
-    \begin{enumerate}
-      \item Complete(100\%) data - Number of students who scored more than 90\% across all regions
-      \item Each slice - Number of students who scored more than 90\% in each subject across all regions
-    \end{enumerate}
+  \frametitle{Structure of the file}
+  Understanding the structure of sslc1.txt
+  \begin{itemize}
+    \item Each line in the file has a student's details(record)
+    \item Each record consists of fields separated by ';'
+  \end{itemize}
+\emphbar{A;015162;JENIL T P;081;060;77;41;74;333;P;;}
 \end{frame}
 
 \begin{frame}
-  \frametitle{Statistical Analysis and Parsing \ldots}
-  Machinery Required -
-  \begin{itemize}
-    \item File reading
-    \item Parsing
-    \item Dictionaries
-    \item NumPy arrays
-    \item Statistical operations
-  \end{itemize}
-\end{frame}
-
-\begin{frame}
-  \frametitle{File reading and parsing}
-  Understanding the structure of sslc1.txt
-  \begin{itemize}
-    \item One line in file corresponds to a student's details
-    \item aka record
-    \item Each record consists of fields separated by ';'
-  \end{itemize}
-\end{frame}
-
-\begin{frame}
-  \frametitle{File reading and parsing \ldots}
+  \frametitle{Structure of the file \ldots}
+\emphbar{A;015163;JOSEPH RAJ S;083;042;47;AA;72;244;;;}
   Each record consists of:
   \begin{itemize}
     \item Region Code
@@ -195,11 +217,43 @@
     \item Marks of 5 subjects: English, Hindi, Maths, Science, Social
     \item Total marks
     \item Pass/Fail (P/F)
-    \item Withdrawn (W)
+    \item Withheld (W)
   \end{itemize}
   \inctime{5}
 \end{frame}
 
+\begin{frame}
+  \frametitle{Statistical Analysis: Problem statement}
+  1. Read the data supplied in the file \emph{sslc1.txt} and carry out the following:
+  \begin{itemize}
+    \item[a] Draw a pie chart representing proportion of students who scored more than 90\% in each region in Science.
+    \item[b] Print mean, median and standard deviation of math scores for all regions combined.
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Problem statement: explanation}
+    \emphbar{a. Draw a pie chart representing proportion of students who scored more than 90\% in each region in Science.}
+\begin{columns}
+    \column{5.25\textwidth}
+    \hspace*{.5in}
+\includegraphics[height=2.6in, interpolate=true]{data/science}
+    \column{0.8\textwidth}
+\end{columns}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Machinery Required}
+  \begin{itemize}
+    \item File reading
+    \item Parsing
+    \item Dictionaries 
+    \item List enumeration
+    \item Arrays
+    \item Statistical operations
+  \end{itemize}
+\end{frame}
+
 \subsection{Data processing}
 \begin{frame}[fragile]
   \frametitle{File reading and parsing \ldots}
@@ -207,100 +261,71 @@
 for record in open('sslc1.txt'):
     fields = record.split(';')
   \end{lstlisting}
+\begin{block}{}
+\centerline{Recall pendulum example!}
+\end{block}
 \end{frame}
 
-\subsection{Dictionary}
+\subsection{Dictionaries}
 \begin{frame}[fragile]
-  \frametitle{Dictionary: Introduction}
+  \frametitle{Dictionaries: Introduction}
   \begin{itemize}
     \item lists index: 0 \ldots n
     \item dictionaries index using strings
   \end{itemize}
-  \begin{block}{Example}
-d = \{ ``Hitchhiker's guide'' : 42,
-     ``Terminator'' : ``I'll be back''\}\\
-d[``Terminator''] => ``I'll be back''
-  \end{block}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Dictionary: Introduction}
+  \frametitle{Dictionaries \ldots}
   \begin{lstlisting}
-In [1]: d = {"Hitchhiker's guide" : 42,
-      "Terminator" : "I'll be back"}
+In []: d = {"jpg" : "image file",
+      "txt" : "text file", 
+      "py" : "python code"}
 
-In [2]: d["Hitchhiker's guide"]
-Out[2]: 42
-
-In [3]: "Hitchhiker's guide" in d
-Out[3]: True
-
-In [4]: "Guido" in d
-Out[4]: False
+In []: d["txt"]
+Out[]: 'text file'
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Dictionary: Introduction}
+  \frametitle{Dictionaries \ldots}
   \begin{lstlisting}
-In [5]: d.keys()
-Out[5]: ['Terminator', "Hitchhiker's 
-                              guide"]
+In []: "py" in d
+Out[]: True
 
-In [6]: d.values()
-Out[6]: ["I'll be back", 42]
+In []: "cpp" in d
+Out[]: False
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Back to lists: Iterating}
-  \begin{itemize}
-    \item Python's \kwrd{for} loop iterates through list items
-    \item In other languages (C/C++) we run through indices and pick items from the array using these indices
-    \item In Python, while iterating through list items current position is not available
-  \end{itemize}
-  \begin{block}{Iterating through indices}
-    What if we want the index of an item of a list?
-  \end{block}
+  \frametitle{Dictionaries \ldots}
+  \begin{lstlisting}
+In []: d.keys()
+Out[]: ['py', 'txt', 'jpg']
 
+In []: d.values()
+Out[]: ['python code', 'text file',
+       'image file']
+  \end{lstlisting}
+  \inctime{10}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{enumerate: Iterating through list indices}
-  \begin{lstlisting}
-In [1]: names = ["Guido","Alex", "Tim"]
-
-In [2]: for i, name in enumerate(names):
-   ...:     print i, name
-   ...: 
-0 Guido
-1 Alex
-2 Tim
-  \end{lstlisting}
-  \inctime{5}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Continuing with our Dictionary}
+  \frametitle{Getting back to the problem}
   Let our dictionary be:
   \begin{lstlisting}
-science = {} # is an empty dictionary
+science = {}
   \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Dictionary - Building parsed data}
-  \begin{itemize}
-    \item \emph{Keys} of \emph{science} will be region codes
-    \item Value of a \emph{science} will be the number students who scored more than 90\% in that region
+\begin{itemize}
+    \item Keys will be region codes
+    \item Values will be the number students who scored more than 90\% in that region
   \end{itemize}
 \end{frame}
 
 \begin{frame}[fragile]
   \frametitle{Building parsed data \ldots}
   \begin{lstlisting}
-from pylab import pie
-
 science = {}
 
 for record in open('sslc1.txt'):
@@ -317,9 +342,9 @@
 if region_code not in science:
     science[region_code] = 0
 
-score_str = fields[4].strip()
+score_str = fields[6].strip()
 
-score = int(score_str) if
+score = int(score_str) if \
     score_str != 'AA' else 0
 
 if score > 90:
@@ -327,17 +352,25 @@
   \end{lstlisting}
 \end{frame}
 
+\begin{frame}[fragile]
+  \frametitle{Building parsed data \ldots}
+  \begin{lstlisting}
+print science
+print science.keys()
+print science.values()
+  \end{lstlisting}
+\end{frame}
+
 \subsection{Visualizing data}
 \begin{frame}[fragile]
-  \frametitle{Pie charts}
+  \frametitle{Pie chart}
   \small
   \begin{lstlisting}
-figure(1)
 pie(science.values(), 
-    labels=science.keys())
+    labels = science.keys())
 title('Students scoring 90% and above 
       in science by region')
-savefig('/tmp/science.png')
+savefig('science.png')
   \end{lstlisting}
 \begin{columns}
     \column{5.25\textwidth}
@@ -345,148 +378,65 @@
 \includegraphics[height=2in, interpolate=true]{data/science}
     \column{0.8\textwidth}
 \end{columns}
-  \inctime{5}
+  \inctime{10}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Problem statement}
+    \emphbar{b. Print mean, median and standard deviation of math scores for all regions combined.}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Building data for all subjects \ldots}
+  \frametitle{Building data for statistics}
   \begin{lstlisting}
-from pylab import pie
-from scipy import mean, median, std
-from scipy import stats
+math_scores = []
 
-scores = [[], [], [], [], []]
-ninety_percents = [{}, {}, {}, {}, {}]
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Building data for all subjects \ldots}
-  \begin{lstlisting}
 for record in open('sslc1.txt'):
     record = record.strip()
     fields = record.split(';')
 
-    region_code = fields[0].strip()
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Building data for all subjects \ldots}
-  \small
-  \begin{lstlisting}
-for i, field in enumerate(fields[3:8]):
-    if region_code not in ninety_percents[i]:
-        ninety_percents[i][region_code] = 0
-
-    score_str = field.strip()
-    score = int(score_str) if
+    score_str = fields[5].strip()
+    score = int(score_str) if \
       score_str != 'AA' else 0
 
-    scores[i].append(score)
-
-    if score > 90:
-        ninety_percents[i][region_code] += 1
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Consolidating data}
-  \begin{lstlisting}
-subj_total = []
-for subject in ninety_percents:
-    subj_total.append(sum(
-         subject.values()))
+    math_scores.append(score)
   \end{lstlisting}
 \end{frame}
 
-\begin{frame}[fragile]
-  \frametitle{Pie charts}
-  \begin{lstlisting}
-figure(2)
-pie(subj_total, labels=['English',
-    'Hindi', 'Maths', 'Science',
-    'Social'])
-title('Students scoring more than
-      90% by subject(All regions
-      combined).')
-savefig('/tmp/all_regions.png')
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Pie charts}
-  \includegraphics[height=3in, interpolate=true]{data/all_regions}
-\end{frame}
-
 \subsection{Obtaining statistics}
 \begin{frame}[fragile]
   \frametitle{Obtaining statistics}
-  \begin{block}{Statistics: Mean}
+  \begin{block}{Exercise}
     Obtain the mean of Math scores
   \end{block}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Obtaining statistics: Solution}
-  \begin{block}{Statistics: Mean}
-    Obtain the mean of Math scores
-  \end{block}
-  \begin{lstlisting}
-math_scores = scores[2]
-total = 0
-for i, score in enumerate(math_scores):
-    total += score
-
-mean = total / (i + 1)
-print "Mean: ", mean
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Obtaining statistics: Another solution}
-  \begin{block}{Statistics: Mean}
-    Obtain the mean of Math scores
-  \end{block}
-  \begin{lstlisting}
-math_scores = scores[2]
-mean = sum(math_scores) /
-          len(math_scores)
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-\frametitle{NumPy arrays}
-  \begin{itemize}
-    \item NumPy provides arrays
-    \item arrays are very efficient and powerful 
-    \item Very easy to perform element-wise operations - \typ{+, -, *, /, \%}
-    \begin{lstlisting}
-In [1]: a = array([1, 2, 3])
-In [2]: b = array([4, 5, 6])
-
-In [3]: a + b
-Out[3]: array([5, 7, 9])
-    \end{lstlisting}
-    \item Very easy to compute statistics
-  \end{itemize}
-\end{frame}
-
-\begin{frame}[fragile]
   \frametitle{Obtaining statistics}
   \begin{lstlisting}
-math_scores = array(scores[2])
-
 print "Mean: ", mean(math_scores)
 
 print "Median: ", median(math_scores)
 
-print "Mode: ", stats.mode(math_scores)
-
 print "Standard Deviation: ",
               std(math_scores)
   \end{lstlisting}
-  \inctime{15}
+  \inctime{10}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Obtaining statistics: efficiently!}
+  \begin{lstlisting}
+math_array = array(math_scores)
+
+print "Mean: ", mean(math_array)
+
+print "Median: ", median(math_array)
+
+print "Standard Deviation: ",
+              std(math_array)
+  \end{lstlisting}
+  \inctime{5}
 \end{frame}
 
 \begin{frame}[fragile]
@@ -494,37 +444,9 @@
   \begin{itemize}
    \item Dictionaries for storing data
    \item Facilities for drawing pie charts
-   \item NumPy arrays for efficient array manipulations
-   \item Functions for statistical computations - mean, median, mode, standard deviation
+   \item Efficient array manipulations
+   \item Functions for statistical computations - mean, median, standard deviation
   \end{itemize}
 \end{frame}
 
-\section{Least square fit}
-\begin{frame}
-\frametitle{L vs $T^2$ \ldots}
-Let's go back to the L vs $T^2$ plot
-\begin{itemize}
-\item We first look at obtaining $T^2$ from T
-\item Then, we look at plotting a Least Squares fit
-\end{itemize}
-\end{frame}
-
-\begin{frame}[fragile]
-\frametitle{Dealing with data whole-sale}
-\begin{lstlisting}
-In []: for t in T:
- ....:     TSq.append(t*t)
-\end{lstlisting}
-\begin{itemize}
-\item This is not very efficient
-\item We are squaring element after element
-\item We use arrays to make this efficient
-\end{itemize}
-\begin{lstlisting}
-In []: L = array(L)
-In []: T = array(T)
-In []: TSq = T*T
-\end{lstlisting}
-\end{frame}
-
 \end{document}
--- a/day2/session1.tex	Fri Nov 06 18:39:56 2009 +0530
+++ b/day2/session1.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -1,8 +1,8 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %Tutorial slides on Python.
 %
-% Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>
-% Copyright (c) 2005-2009, Prabhu Ramachandran
+% Author: FOSSEE 
+% Copyright (c) 2009, FOSSEE, IIT Bombay
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 \documentclass[14pt,compress]{beamer}
@@ -78,7 +78,7 @@
 \author[FOSSEE Team] {The FOSSEE Group}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {1, November 2009\\Day 2, Session 1}
+\date[] {8 November, 2009\\Day 2, Session 1}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 %\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
@@ -140,13 +140,13 @@
   \begin{itemize}
     \item \kwrd{int}\\ \kwrd{int} = whole number, no matter what the size!
   \begin{lstlisting}
-In [1]: a = 13
+In []: a = 13
 
-In [2]: b = 99999999999999999999
+In []: b = 99999999999999999999
   \end{lstlisting}
     \item \kwrd{float}
   \begin{lstlisting}
-In [3]: fl = 3.141592
+In []: p = 3.141592
   \end{lstlisting}
   \end{itemize}
 \end{frame}
@@ -154,16 +154,16 @@
 \begin{frame}[fragile]
 \frametitle{Complex numbers}
   \begin{lstlisting}
-In [1]: cplx = 3+4j
+In []: c = 3+4j
 
-In [2]: abs(cplx)
-Out[2]: 5.0
+In []: abs(c)
+Out[]: 5.0
 
-In [3]: cplx.imag
-Out[3]: 4.0
+In []: c.imag
+Out[]: 4.0
 
-In [4]: cplx.real
-Out[4]: 3.0
+In []: c.real
+Out[]: 3.0
   \end{lstlisting}
 \end{frame}
 
@@ -171,16 +171,31 @@
 \begin{frame}[fragile]
   \frametitle{Boolean}
   \begin{lstlisting}
-In [1]: t = True
+In []: t = True
+
+In []: f = not t
 
-In [2]: f = not t
-Out[2]: False
+In []: f or t
+Out[]: True
+
+In []: f and t
+Out[]: False
+  \end{lstlisting}
+  \inctime{5}
+\end{frame}
 
-In [3]: f or t
-Out[3]: True
+\begin{frame}[fragile]
+  \frametitle{( )  for precedence}
+  \begin{lstlisting}
+In []: a = False
+In []: b = True
+In []: c = True
 
-In [4]: f and t
-Out[4]: False
+In []: (a and b) or c
+Out[]: True
+
+In []: a and (b or c)
+Out[]: False
   \end{lstlisting}
   \inctime{5}
 \end{frame}
@@ -191,20 +206,20 @@
   \frametitle{Strings}
 Strings were introduced previously, let us now look at them in a little more detail.
   \begin{lstlisting}
-In [1]: w = "hello"
+In []: w = "hello"
 
-In [2]: print w[0] + w[2] + w[-1]
-Out[2]: hlo
+In []: print w[0] + w[2] + w[-1]
+Out[]: hlo
 
-In [3]: len(w) # guess what
-Out[3]: 5
+In []: len(w) # guess what
+Out[]: 5
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
   \frametitle{Strings \ldots}
   \begin{lstlisting}
-In [1]: w[0] = 'H' # Can't do that!
+In []: w[0] = 'H' # Can't do that!
 --------------------------------------------
 TypeError  Traceback (most recent call last)
 
@@ -218,19 +233,35 @@
 \begin{frame}[fragile]
   \frametitle{String methods}
   \begin{lstlisting}
-In [1]: a = 'Hello World'
-In [2]: a.startswith('Hell')
-Out[2]: True
+In []: a = 'Hello World'
+In []: a.startswith('Hell')
+Out[]: True
+
+In []: a.endswith('ld')
+Out[]: True
 
-In [3]: a.endswith('ld')
-Out[3]: True
+In []: a.upper()
+Out[]: 'HELLO WORLD'
+
+In []: a.lower()
+Out[]: 'hello world'
+  \end{lstlisting}
+\end{frame}
 
-In [4]: a.upper()
-Out[4]: 'HELLO WORLD'
-
-In [5]: a.lower()
-Out[5]: 'hello world'
-  \end{lstlisting}
+\begin{frame}
+  \frametitle{A bit about IPython}
+  \begin{itemize}
+    \item IPython provides better help
+    \item object.function?
+    \begin{lstlisting}
+In []: a = 'Hello World'
+In []: a.lower?
+    \end{lstlisting}
+    \item It provides tab completion
+        \begin{lstlisting}
+In []: a.s<Tab>
+    \end{lstlisting}
+  \end{itemize}
 \end{frame}
 
 \begin{frame}[fragile]
@@ -240,77 +271,102 @@
     \item join() is the opposite of split()
   \end{itemize}
   \begin{lstlisting}
-In [1]: ''.join(['a', 'b', 'c'])
-Out[1]: 'abc'
+In []: ''.join(['a', 'b', 'c'])
+Out[]: 'abc'
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
 \frametitle{String formatting}
   \begin{lstlisting}
-In [1]: x, y = 1, 1.234
+In []: x, y = 1, 1.234
 
-In [2]: 'x is %s, y is %s' %(x, y)
-Out[2]: 'x is 1, y is 1.234'
+In []: 'x is %s, y is %s' %(x, y)
+Out[]: 'x is 1, y is 1.234'
   \end{lstlisting}
+  \begin{itemize}
+    \item \emph{\%d}, \emph{\%f} etc. available
+  \end{itemize}
   \emphbar{\url{http://docs.python.org/library/stdtypes.html}}
   \inctime{10}
 \end{frame}
 
 \section{Operators}
 \begin{frame}[fragile]
-  \frametitle{Arithematic operators}
+  \frametitle{Arithmetic operators}
   \begin{lstlisting}
-In [1]: 1786 % 12
-Out[1]: 10
+In []: 1786 % 12
+Out[]: 10
+
+In []: 45 % 2
+Out[]: 1
 
-In [2]: 3124 * 126789
-Out[2]: 396088836
+In []: 864675 % 10
+Out[]: 5
 
-In [3]: a = 3124 * 126789
+In []: 3124 * 126789
+Out[]: 396088836
 
-In [4]: big = 1234567891234567890 ** 3
+In []: big = 1234567891234567890 ** 3
 
-In [5]: verybig = big * big * big * big
+In []: verybig = big * big * big * big
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Arithematic operators \ldots}
+  \frametitle{Arithmetic operators}
   \begin{lstlisting}
-In [1]: 17/2
-Out[1]: 8
+In []: 17 / 2
+Out[]: 8
+
+In []: 17 / 2.0
+Out[]: 8.5
+
+In []: 17.0 / 2
+Out[]: 8.5
+
+In []: 17.0 / 8.5
+Out[]: 2.0
+  \end{lstlisting}
+\end{frame}
 
-In [2]: 17/2.0
-Out[2]: 8.5
+\begin{frame}[fragile]
+  \frametitle{Arithmetic operators}
+  \begin{lstlisting}
+In []: a = 7546
 
-In [3]: 17.0/2
-Out[3]: 8.5
+In []: a += 1
+In []: a
+Out[]: 7547
 
-In [4]: 17.0/8.5
-Out[4]: 2.0
+In []: a -= 5
+In []: a
+
+In []: a *= 2
+
+In []: a /= 5
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
   \frametitle{String operations}
   \begin{lstlisting}
-In [1]: s = 'Hello '
+In []: s = 'Hello '
 
-In [2]: p = 'World'
+In []: p = 'World'
 
-In [3]: s + p 
-Out[3]: 'Hello World'
+In []: s + p 
+Out[]: 'Hello World'
 
-In [4]: s * 4
-Out[4]: 'Hello Hello Hello Hello'
+In []: s * 4
+Out[]: 'Hello Hello Hello Hello'
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
   \frametitle{String operations \ldots}
   \begin{lstlisting}
-In [1]: s * s
+In []: s * s
 --------------------------------------------
 TypeError  Traceback (most recent call last)
 
@@ -324,35 +380,35 @@
 \begin{frame}[fragile]
   \frametitle{Relational and logical operators}
   \begin{lstlisting}
-In [1]: pos, zer, neg = 1, 0, -1
-In [2]: pos == neg
-Out[2]: False
+In []: p, z, n = 1, 0, -1
+In []: p == n
+Out[]: False
 
-In [3]: pos >= neg
-Out[3]: True
+In []: p >= n
+Out[]: True
 
-In [4]: neg < zer < pos
-Out[4]: True
+In []: n < z < p
+Out[]: True
 
-In [5]: pos + neg != zer
-Out[5]: False
+In []: p + n != z
+Out[]: False
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
   \frametitle{Built-ins}
   \begin{lstlisting}
-In [1]: int(17/2.0)
-Out[1]: 8
+In []: int(17 / 2.0)
+Out[]: 8
 
-In [2]: float(17/2)  # Recall
-Out[2]: 8.0
+In []: float(17 / 2)  # Recall
+Out[]: 8.0
 
-In [3]: str(17/2.0)
-Out[3]: '8.5'
+In []: str(17 / 2.0)
+Out[]: '8.5'
 
-In [4]: round( 7.5 )
-Out[4]: 8.0
+In []: round( 7.5 )
+Out[]: 8.0
   \end{lstlisting}
 \end{frame}
 
@@ -362,15 +418,15 @@
     \item Case sensitive
     \item Dynamically typed $\Rightarrow$ need not specify a type
       \begin{lstlisting}
-In [1]: a = 1
-In [2]: a = 1.1
-In [3]: a = "Now I am a string!"
+In []: a = 1
+In []: a = 1.1
+In []: a = "Now I am a string!"
       \end{lstlisting}
     \item Comments:
       \begin{lstlisting}
-In [4]: a = 1  # In-line comments
-In [5]: # A comment line.
-In [6]: a = "# Not a comment!"
+In []: a = 1  # In-line comments
+In []: # A comment line.
+In []: a = "# Not a comment!"
       \end{lstlisting}
   \end{itemize}
   \inctime{15}
@@ -379,14 +435,15 @@
 \section{Simple IO}
 \begin{frame}[fragile]
   \frametitle{Simple IO: Console Input}
+  \small
   \begin{itemize}
     \item raw\_input() waits for user input.
       \begin{lstlisting}
-In [1]: a = raw_input()
+In []: a = raw_input()
 5
 
-In [2]: a = raw_input('prompt > ')
-prompt > 5
+In []: a = raw_input('Enter a value: ')
+Enter a value: 5
       \end{lstlisting}
     \item Prompt string is optional.
     \item All keystrokes are Strings!
@@ -394,11 +451,36 @@
   \end{itemize}
 \end{frame}
 
-\begin{frame}{Simple IO: Console output}
+\begin{frame}[fragile]
+  \frametitle{Simple IO: Console output}
   \begin{itemize}
     \item \texttt{print} is straight forward
-    \item Note the distinction between \texttt{print x} and \texttt{print x,}
+    \item Put the following code snippet in a file
   \end{itemize}
+  \begin{lstlisting}
+print "Hello"
+print "World"
+
+
+In []: %run -i hello1.py
+Hello
+World
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Simple IO: Console output \ldots}
+Put the following code snippet in a file
+  \begin{lstlisting}
+print "Hello",
+print "World"
+
+
+In []: %run -i hello2.py
+Hello World
+  \end{lstlisting}
+
+\emphbar{Note the distinction between \texttt{print x} and \texttt{print x,}}
 \end{frame}
 
 \section{Control flow}
@@ -406,8 +488,9 @@
   \frametitle{Control flow constructs}  
   \begin{itemize}
   \item \kwrd{if/elif/else}: branching
+  \item \kwrd{C if X else Y}: Ternary conditional operator
   \item \kwrd{while}: looping
-  \item \kwrd{for}: iterating 
+  \item \kwrd{for}: iterating
   \item \kwrd{break, continue}: modify loop 
   \item \kwrd{pass}: syntactic filler
   \end{itemize}
@@ -416,101 +499,41 @@
 \subsection{Basic Conditional flow}
 \begin{frame}[fragile]
   \frametitle{\typ{If...elif...else} example}
+  \small
   \begin{lstlisting}
-x = int(raw_input("Enter an integer:"))
-if x < 0:
-     print 'Be positive!'
-elif x == 0:
-     print 'Zero'
-elif x == 1:
-     print 'Single'
-else:
-     print 'More'
+In []: x = int(raw_input("Enter an integer:"))
+
+In []: if x < 0:
+  ...:     print 'Be positive!'
+  ...: elif x == 0:
+  ...:     print 'Zero'
+  ...: elif x == 1:
+  ...:     print 'Single'
+  ...: else:
+  ...:     print 'More'
+  ...:
+  ...:
   \end{lstlisting}
   \inctime{10}
 \end{frame}
 
-\subsection{Basic Looping}
 \begin{frame}[fragile]
-  \frametitle{\typ{while}}
-Example: Fibonacci series
-  \begin{lstlisting}
-# the sum of two elements
-# defines the next
-a, b = 0, 1
-while b < 10:
-    print b,
-    a, b = b, a + b 
-\end{lstlisting}
-\typ{1 1 2 3 5 8}\\  
-\end{frame}
-
-\begin{frame}[fragile]
-\frametitle{\typ{range()}}
-\kwrd{range([start,] stop[, step])}\\
-\begin{itemize}
-  \item range() returns a list of integers
-  \item The \emph{start} and the \emph{step} arguments are optional
-  \item \emph{stop} argument is not included in the list
-\end{itemize}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{\typ{for} \ldots \typ{range()}}
-Example: print squares of first \typ{n} numbers
+  \frametitle{Ternary conditional operator}
   \begin{lstlisting}
-In []: for i in range(5):
- ....:     print i, i * i
- ....:
- ....:
-0 0
-1 1
-2 4
-3 9
-4 16
-\end{lstlisting}
-\inctime{5}
-\end{frame}
-
-\subsection{Exercises}
-
-\begin{frame}{Problem set 1: Problem 1.1}
-  Write a program that displays all three digit numbers that are equal to the sum of the cubes of their digits. That is, print numbers $abc$ that have the property $abc = a^3 + b^3 + c^3$\\
-\vspace*{0.2in}
-\emphbar{These are called $Armstrong$ numbers.}
-\end{frame}
-
-\begin{frame}{Problem 1.2 - Collatz sequence}
-\begin{enumerate}
-  \item Start with an arbitrary (positive) integer. 
-  \item If the number is even, divide by 2; if the number is odd, multiply by 3 and add 1.
-  \item Repeat the procedure with the new number.
-  \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 1.3}
-  Write a program that prints the following pyramid on the screen. 
-  \begin{lstlisting}
-1
-2  2
-3  3  3
-4  4  4  4
+...
+a = raw_input('Enter number(Q to quit):')
+num = int(a) if a != 'Q' else break
+...
   \end{lstlisting}
-The number of lines must be obtained from the user as input.\\
-\pause
-\emphbar{When can your code fail?}
-\inctime{5}
 \end{frame}
 
 \begin{frame}[fragile]
   \frametitle{What did we learn?}
   \begin{itemize}
-    \item Basic data types
-    \item Operators
-    \item Conditional structures
-    \item Loops
+    \item Data types: int, float, complex, boolean, string
+    \item Operators: +, -, *, /, \%, **, +=, -=, *=, /=, >, <, <=, >=, ==, !=, a < b < c
+    \item Simple IO: \kwrd{raw\_input} and \kwrd{print}
+    \item Conditional structures: \kwrd{if/elif/else},\\ \kwrd{C if X else Y}
   \end{itemize}
 \end{frame}
 
--- a/day2/session2.tex	Fri Nov 06 18:39:56 2009 +0530
+++ b/day2/session2.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -1,8 +1,8 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %Tutorial slides on Python.
 %
-% Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>
-% Copyright (c) 2005-2009, Prabhu Ramachandran
+% Author: FOSSEE 
+% Copyright (c) 2009, FOSSEE, IIT Bombay
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 \documentclass[14pt,compress]{beamer}
@@ -78,7 +78,7 @@
 \author[FOSSEE Team] {The FOSSEE Group}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {1, November 2009\\Day 2, Session 2}
+\date[] {8 November, 2009\\Day 2, Session 2}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 %\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
@@ -123,13 +123,113 @@
   % You might wish to add the option [pausesections]
 \end{frame}
 
+\section{Control flow}
+\subsection{Basic Looping}
+\begin{frame}[fragile]
+  \frametitle{\typ{while}}
+Example: Fibonacci series
+  \begin{lstlisting}
+# the sum of two elements
+# defines the next
+In []: a, b = 0, 1
+In []: while b < 10:
+  ...:     print b,
+  ...:     a, b = b, a + b
+  ...:
+  ...:
+\end{lstlisting}
+\typ{1 1 2 3 5 8}\\
+\end{frame}
+
+\begin{frame}[fragile]
+\frametitle{\typ{range()}}
+\kwrd{range([start,] stop[, step])}\\
+\begin{itemize}
+  \item range() returns a list of integers
+  \item The \emph{start} and the \emph{step} arguments are optional
+  \item \emph{stop} argument is not included in the list
+\end{itemize}
+\vspace*{.5in}
+\begin{itemize}
+  \item \alert{Anything within \typ{[]} is optional}
+  \begin{itemize}
+    \item Nothing to do with Python.
+  \end{itemize}
+\end{itemize}
+
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{\typ{for} \ldots \typ{range()}}
+Example: print squares of first \typ{n} numbers
+  \begin{lstlisting}
+In []: for i in range(5):
+ ....:     print i, i * i
+ ....:
+ ....:
+0 0
+1 1
+2 4
+3 9
+4 16
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{\typ{for} \ldots \typ{range()}}
+Example: print squares of odd numbers from 3 to 9
+  \begin{lstlisting}
+In []: for i in range(3, 10, 2):
+ ....:     print i, i * i
+ ....:
+ ....:
+3 9
+5 25
+7 49
+9 81
+\end{lstlisting}
+\inctime{5}
+\end{frame}
+
+\subsection{Exercises}
+
+\begin{frame}{Problem set 1: Problem 1.1}
+  Write a program that displays all three digit numbers that are equal to the sum of the cubes of their digits. That is, print numbers $abc$ that have the property $abc = a^3 + b^3 + c^3$\\
+\vspace*{0.2in}
+\emphbar{These are called $Armstrong$ numbers.}
+\end{frame}
+
+\begin{frame}{Problem 1.2 - Collatz sequence}
+\begin{enumerate}
+  \item Start with an arbitrary (positive) integer. 
+  \item If the number is even, divide by 2; if the number is odd, multiply by 3 and add 1.
+  \item Repeat the procedure with the new number.
+  \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 1.3}
+  Write a program that prints the following pyramid on the screen. 
+  \begin{lstlisting}
+1
+2  2
+3  3  3
+4  4  4  4
+  \end{lstlisting}
+The number of lines must be obtained from the user.\\
+\pause
+\emphbar{When can your code fail?}
+\inctime{5}
+\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]
+num = [1, 2, 3, 4]
   \end{lstlisting}
 \centerline{is a list}
 \end{block}
@@ -138,29 +238,76 @@
 \begin{frame}[fragile]
   \frametitle{Lists: methods}
   \begin{lstlisting}
+In []: num = [1, 2, 3, 4]
+
+In []: num.append([9, 10, 11])
+
+In []: num
+Out[]: [1, 2, 3, 4, [9, 10, 11]]
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Lists: methods}
+  \begin{lstlisting}
+In []: num = [1, 2, 3, 4]
+
+In []: num.extend([5, 6, 7])
+In []: num
+Out[]: [1, 2, 3, 4, 5, 6, 7]
+
 In []: num.reverse()
 In []: num
-Out[]: [8, 7, 6, 5, 4, 3, 2, 1]
+Out[]: [7, 6, 5, 4, 3, 2, 1]
 
-In []: num.extend([0, -1, -2])
+In []: num.remove(6)
 In []: num
-Out[]: [8, 7, 6, 5, 4, 3, 2, 1, 0, -1]
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Lists: slicing}
+  \begin{itemize}
+    \item \typ{list[initial:final]}
+  \end{itemize}
+\begin{lstlisting}
+In []: a = [1, 2, 3, 4, 5]
+
+In []: a[1:3]
+Out[]: [2, 3]
+
+In []: a[1:-1]
+Out[]: [2, 3, 4]
 
-In []: num.remove(0)
-In []: num
-Out[]: [8, 7, 6, 5, 4, 3, 2, 1, -1]
-  \end{lstlisting}
+In []: a[:3]
+Out[]: [1, 2, 3]
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Lists: slicing}
+  \begin{itemize}
+    \item \typ{list[initial:final:step]}
+  \end{itemize}
+\begin{lstlisting}
+In []: a[1:-1:2]
+Out[]: [2, 4]
+
+In []: a[::2]
+Out[]: [1, 3, 5]
+
+In []: a[-1::-1]
+Out[]: [5, 4, 3, 2, 1]
+\end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
 \frametitle{List containership}
 \begin{lstlisting}
-In []: a = 8
-
-In []: a in num
+In []: 4 in num
 Out[]: True
 
-In []: b = 10
+In []: b = 15
 In []: b in num
 Out[]: False
 
@@ -174,9 +321,14 @@
 \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
+
+# Try the following!
+In []: t[4] = 7 
 \end{lstlisting}
+\pause
 \begin{block}{Note:}
 \begin{itemize}
   \item Tuples are immutable - cannot be changed
@@ -200,7 +352,7 @@
 
 \subsection{Dictionaries}
 \begin{frame}[fragile]
-  \frametitle{Dictionaries: Recall}
+  \frametitle{Dictionaries: recall}
   \begin{lstlisting}
 In []: player = {'Mat': 134,'Inn': 233,
           'Runs': 10823, 'Avg': 52.53}
@@ -214,6 +366,28 @@
   \end{block}
 \end{frame}
 
+\begin{frame}[fragile]
+  \frametitle{Dictionaries: containership}
+  \begin{lstlisting}
+In []: 'Inn' in player
+Out[]: True
+
+In []: 'Econ' in player
+Out[]: False
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Dictionaries: methods}
+  \begin{lstlisting}
+In []: player.keys()
+Out[]: ['Runs', 'Inn', 'Avg', 'Mat']
+
+In []: player.values()
+Out[]: [10823, 233, 52.530000000000001, 134]
+  \end{lstlisting}
+\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}
@@ -228,32 +402,47 @@
       \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])
+
+In []: f10 = set([1,2,3,5,8])
+
+In []: p10 = set([2,3,5,7])
+
+In []: f10 | p10
+Out[]: set([1, 2, 3, 5, 7, 8])
 \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Set}
+  \frametitle{Set \ldots}
     \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
+In []: f10 & p10
+Out[]: set([2, 3, 5])
+
+In []: f10 - p10
+Out[]: set([1, 8])
+
+In []: p10 - f10, f10 ^ p10
+Out[]: (set([7]), set([1, 7, 8]))
+
+In []: set([2,3]) < p10
+Out[]: True
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Set \ldots}
+    \begin{lstlisting}
+In []: set([2,3]) <= p10
+Out[]: True
+
+In []: 2 in p10
+Out[]: True
+
+In []: 4 in p10
+Out[]: False
+
+In []: len(f10)
+Out[]: 5
 \end{lstlisting}
 \end{frame}
 
@@ -261,7 +450,14 @@
   \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 missing numbers in the given range.
+\end{description}
+\inctime{15}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Problem set 2.2}
+  \begin{description}
+    \item[2.2.2] Given a list of words, find all the anagrams in the list
 \end{description}
 \inctime{15}
 \end{frame}
@@ -294,6 +490,19 @@
 \end{frame}
 
 \begin{frame}[fragile]
+  \frametitle {What does this function do?}
+  \begin{lstlisting}
+def what( n ):
+    if n < 0: n = -n
+    while n > 0:
+        if n % 2 == 1:
+            return False
+        n /= 10
+    return True
+  \end{lstlisting}
+\end{frame} 
+
+\begin{frame}[fragile]
   {What does this function do?}
 \begin{lstlisting}
 def what( n ):
@@ -304,219 +513,13 @@
   \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 "<stdin>", line 1, in <module>
-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}
+  \frametitle{What did we learn?}
   \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
+    \item Loops: \kwrd{while}, \kwrd{for}
+    \item Advanced Data structures
+    \item Functions
   \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}
+\end{document}
\ No newline at end of file
--- a/day2/session3.tex	Fri Nov 06 18:39:56 2009 +0530
+++ b/day2/session3.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -1,48 +1,33 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-% Tutorial slides on Python.
+%Tutorial slides on Python.
 %
-% Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>
-% Copyright (c) 2005-2009, Prabhu Ramachandran
+% Author: FOSSEE 
+% Copyright (c) 2009, FOSSEE, IIT Bombay
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-\documentclass[compress,14pt]{beamer}
-% \documentclass[handout]{beamer}
-% \usepackage{pgfpages}
-% \pgfpagesuselayout{4 on 1}[a4paper,border, shrink=5mm,landscape]
-\usepackage{tikz}
-\newcommand{\hyperlinkmovie}{}
-%\usepackage{movie15}
+\documentclass[14pt,compress]{beamer}
+%\documentclass[draft]{beamer}
+%\documentclass[compress,handout]{beamer}
+%\usepackage{pgfpages} 
+%\pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm]
 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-% Note that in presentation mode 
-% \paperwidth  364.19536pt
-% \paperheight 273.14662pt
-% h/w = 0.888
-
-
+% Modified from: generic-ornate-15min-45min.de.tex
 \mode<presentation>
 {
   \usetheme{Warsaw}
-  %\usetheme{Boadilla}
-  %\usetheme{default}
   \useoutertheme{infolines}
   \setbeamercovered{transparent}
 }
 
-% To remove navigation symbols
-\setbeamertemplate{navigation symbols}{}
-
-\usepackage{amsmath}
 \usepackage[english]{babel}
 \usepackage[latin1]{inputenc}
-\usepackage{times}
+%\usepackage{times}
 \usepackage[T1]{fontenc}
 
 % Taken from Fernando's slides.
 \usepackage{ae,aecompl}
 \usepackage{mathpazo,courier,euler}
 \usepackage[scaled=.95]{helvet}
-\usepackage{pgf}
 
 \definecolor{darkgreen}{rgb}{0,0.5,0}
 
@@ -55,65 +40,50 @@
   keywordstyle=\color{blue}\bfseries}
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-% My Macros
-\setbeamercolor{postit}{bg=yellow,fg=black}
+% Macros
 \setbeamercolor{emphbar}{bg=blue!20, fg=black}
 \newcommand{\emphbar}[1]
 {\begin{beamercolorbox}[rounded=true]{emphbar} 
       {#1}
  \end{beamercolorbox}
 }
-%{\centerline{\fcolorbox{gray!50} {blue!10}{
-%\begin{minipage}{0.9\linewidth}
-%    {#1} 
-%\end{minipage}
-%    }}}
-
-\newcommand{\myemph}[1]{\structure{\emph{#1}}}
-\newcommand{\PythonCode}[1]{\lstinline{#1}}
-
-\newcommand{\tvtk}{\texttt{tvtk}}
-\newcommand{\mlab}{\texttt{mlab}}
-
 \newcounter{time}
 \setcounter{time}{0}
-\newcommand{\inctime}[1]{\addtocounter{time}{#1}{\vspace*{0.1in}\tiny \thetime\ m}}
+\newcommand{\inctime}[1]{\addtocounter{time}{#1}{\tiny \thetime\ m}}
+
+\newcommand{\typ}[1]{\texttt{#1}}
+
+\newcommand{\kwrd}[1]{ \texttt{\textbf{\color{blue}{#1}}}  }
 
-\newcommand\BackgroundPicture[1]{%
-  \setbeamertemplate{background}{%
-      \parbox[c][\paperheight]{\paperwidth}{%
-      \vfill \hfill
- \hfill \vfill
-}}}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-% Configuring the theme
-%\setbeamercolor{normal text}{fg=white}
-%\setbeamercolor{background canvas}{bg=black}
-
+%%% 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[3D Plotting]{3D data Visualization}
+\title[Basic Python]{Python language: Data structures and functions}
 
-\author[FOSSEE] {FOSSEE}
+\author[FOSSEE Team] {The FOSSEE Group}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {1 November, 2009\\Day 2, Session 5}
-
+\date[] {8 November, 2009\\Day 2, Session 3}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-%\pgfdeclareimage[height=0.75cm]{iitblogo}{iitblogo}
-%\logo{\pgfuseimage{iitblogo}}
+%\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
+%\logo{\pgfuseimage{iitmlogo}}
 
-\AtBeginSection[]
-{
-  \begin{frame}<beamer>
-    \frametitle{Outline}      
-    \tableofcontents[currentsection,currentsubsection]
-  \end{frame}
-}
 
 %% Delete this, if you do not want the table of contents to pop up at
 %% the beginning of each subsection:
@@ -132,12 +102,19 @@
     \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
+  \titlepage
 \end{frame}
 
 \begin{frame}
@@ -146,413 +123,325 @@
   % You might wish to add the option [pausesections]
 \end{frame}
 
-\section{3D Data Visualization}
+\section{Functions}
+\subsection{Default arguments}
+\begin{frame}[fragile]
+  \frametitle{Functions: default arguments}
+  \begin{lstlisting}
+In []: greet = 'hello world'
 
-\begin{frame}
-    \frametitle{What is visualization?}
-    \Large
-    \begin{center}
-    Visual representation of data
-    \end{center}
+In []: greet.split()
+Out[]: ['hello', 'world']
+
+In []: line = 'Rossum, Guido, 54, 46, 55'
+
+In []: line.split(',')
+Out[]: ['Rossum', ' Guido', ' 54',
+                        ' 46', ' 55']
+  \end{lstlisting}
 \end{frame}
 
+\begin{frame}[fragile]
+  \frametitle{Functions: default arguments \ldots}
+  \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
 
-%% \begin{frame}
-%%     \frametitle{Is this new?}    
-%%     \begin{center}
-%%     We have moved from:
-%%     \end{center}
-%%     \begin{columns}
-%%     \column{}
-%%     \hspace*{-1in}    
-%%     \includegraphics[width=1.75in,height=1.75in, interpolate=true]{data/3832}      
-%%     \column{}\hspace*{-0.25in}
-%%     To
-%%     \column{}
-%%     \hspace*{-1in}
-%%     \includegraphics[width=1.75in, height=1.75in, interpolate=true]{data/torus}  
-%%     \end{columns}
-%% \end{frame}
+ask_ok('?')
+ask_ok('?', '[Y/N]')
+  \end{lstlisting}
+\end{frame} 
 
-\begin{frame}
-    \frametitle{3D visualization}
-    \Large
-    \begin{center}
-        Harder but important
-    \end{center}
+\subsection{Keyword arguments}
+\begin{frame}[fragile]
+  \frametitle{Functions: Keyword arguments}
+We have seen the following
+  \begin{lstlisting}
+In []: legend(['sin(2y)'],
+              loc='center')
+In []: plot(y, sin(y), 'g',
+                 linewidth=2)
+In []: annotate('local max',
+                 xy=(1.5, 1))
+In []: pie(science.values(),
+            labels=science.keys())
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Functions: keyword arguments \ldots}
+  \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(prompt='?')
+ask_ok(prompt='?', complaint='[y/n]')
+ask_ok(complaint='[y/n]', prompt='?')
+\end{lstlisting}
 \end{frame}
 
+\subsection{Built-in functions}
 \begin{frame}
-    \frametitle{Is this Graphics?}
-    \Large
-    \begin{center}
-        Visualization is about data!
-    \end{center}
+  {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}
-    \frametitle{Examples: trajectory in space}
-    \Large
-    \begin{center}
-        \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex}
-    \end{center}
+\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]
+  \frametitle{\typ{from} \ldots \typ{import} magic}
+  \begin{lstlisting}
+from scipy.interpolate import splrep
+from scipy.interpolate import splev
+
+from scipy.integrate import quad
+from scipy.integrate import odeint
+
+from scipy.optimize import fsolve
+  \end{lstlisting}
+\emphbar{All the above statements import one function into your namespace}
 \end{frame}
 
-\begin{frame}
-    \frametitle{Examples: Fire in a room}
-    \Large
-    \begin{center}
-        Demo of data
-    \end{center}
-\inctime{10}
+\begin{frame}[fragile]
+  \frametitle{Running scripts from command line}
+  \small
+  \begin{itemize}
+    \item Start cmd
+    \item cd to Desktop
+    \item python sine\_plot.py
+  \end{itemize}
+  \pause
+  \begin{lstlisting}
+Traceback (most recent call last):
+  File "sine_plot.py", line 1, in <module>
+    x = linspace(-5*pi, 5*pi, 500)
+NameError: name 'linspace' is not defined
+  \end{lstlisting}
 \end{frame}
 
-\section{Tools available}
-
-\subsection{mlab}
+\begin{frame}[fragile]
+  \frametitle{Remedy}
+  \emphbar{Adding what lines to sine\_plot.py makes this program work?}
+  \begin{lstlisting}
+from scipy import *
+  \end{lstlisting}
+\alert{Now run python sine\_plot.py again!}
+  \pause
+  \begin{lstlisting}
+Traceback (most recent call last):
+  File "sine_plot.py", line 4, in <module>
+    plot(x, x, 'b')
+NameError: name 'plot' is not defined
+  \end{lstlisting}
+\end{frame}
 
-\begin{frame}
-    {Overview}
-    \Large
-    \begin{itemize}
-        \item Simple
-        \item Convenient
-        \item Full-featured
+\begin{frame}[fragile]
+  \frametitle{Remedy \ldots}
+  \emphbar{What should we add now?}
+  \begin{lstlisting}
+from pylab import *
+  \end{lstlisting}
+\alert{Now run python sine\_plot.py again!!}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Modules}
+  \begin{itemize}
+    \item The \kwrd{import} keyword ``loads'' a module
+    \item One can also use:
+      \begin{lstlisting}
+In []: from scipy import *
+In []: from scipy import linspace
+      \end{lstlisting}    
+    \item What is the difference?
+    \item \alert{Use the former only in interactive mode}
     \end{itemize}
 \end{frame}
 
 \begin{frame}[fragile]
-
-    \frametitle{Getting started}
-    \myemph{\Large Vanilla:}
-    \begin{lstlisting}[language=bash]
-        $ ipython -wthread
-    \end{lstlisting}
-    \myemph{\Large with Pylab:}
-    \begin{lstlisting}[language=bash]
-        $ ipython -pylab -wthread
-    \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-    \frametitle{Using mlab}
-
-    \begin{lstlisting}
-In []:from enthought.mayavi import mlab
-    \end{lstlisting}
-
-    \vspace*{0.5in}
-
-    \myemph{\Large Try these}
-
-    \vspace*{0.25in}
-
-    \begin{lstlisting}
-In []: mlab.test_<TAB>
-In []: mlab.test_contour3d()
-In []: mlab.test_contour3d??
-    \end{lstlisting}
-\end{frame}
-
-\begin{frame}
-    {Exploring the view}
-    \begin{columns}
-        \column{0.6\textwidth}
-    \pgfimage[width=3in]{MEDIA/m2/contour3d}
-        \column{0.4\textwidth}
-        \begin{itemize}
-            \item Mouse
-            \item Keyboard
-            \item Toolbar
-            \item Mayavi icon\pgfimage[width=0.2in]{MEDIA/m2/m2_icon}
-        \end{itemize}
-    \end{columns}
-\end{frame}
-
-\begin{frame}[fragile]
-    \frametitle{\mlab\ plotting functions}
-    \begin{columns}
-        \column{0.25\textwidth}
-        \myemph{\Large 0D data}
-        \column{0.5\textwidth}
-    \pgfimage[width=2in]{MEDIA/m2/mlab/points3d_ex}
-    \end{columns}
-
-    \begin{lstlisting}
-In []: t = linspace(0, 2*pi, 50)
-In []: u = cos(t) * pi
-In []: x, y, z = sin(u), cos(u), sin(t)
-    \end{lstlisting}
-    \emphbar{\PythonCode{In []: mlab.points3d(x, y, z)}}
-\end{frame}
-
-\begin{frame}
-  \begin{columns}
-        \column{0.25\textwidth}
-        \myemph{\Large 1D data}
-        \column{0.5\textwidth}
-        \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex}
-  \end{columns}
-  \emphbar{\PythonCode{In []: mlab.plot3d(x, y, z, t)}}
+  \frametitle{Package hierarchies}
+  \begin{lstlisting}
+from scipy.interpolate import splev
 
-    Plots lines between the points
-    
-\end{frame}
-
-\begin{frame}[fragile]
-    \begin{columns}
-        \column{0.25\textwidth}
-        \myemph{\Large 2D data}
-        \column{0.5\textwidth}
-        \pgfimage[width=2in]{MEDIA/m2/mlab/surf_ex}
-    \end{columns}            
-    \begin{lstlisting}
-In []: x, y = mgrid[-3:3:100j,-3:3:100j]
-In []: z = sin(x*x + y*y)
-    \end{lstlisting}
-
-    \emphbar{\PythonCode{In []: mlab.surf(x, y, z)}}
-
-    \alert{Assumes the points are rectilinear}
-
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{mgrid}
-  \begin{lstlisting}
-In []: mgrid[0:3,0:3]
-Out[]: 
-array([[[0, 0, 0],
-        [1, 1, 1],
-        [2, 2, 2]],
-
-       [[0, 1, 2],
-        [0, 1, 2],
-        [0, 1, 2]]])
+from scipy.integrate import quad
 
-In []: mgrid[-1:1:5j]
-Out[]: array([-1., -0.5,  0.,  0.5,  1.])
-\end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Example}
-  \begin{lstlisting}
-In []: x, y = mgrid[-1:1:5j, -1:1:5j]
-In []: z = x*x + y*y
-
-In []: z
-Out[]: 
-array([[ 2.  , 1.25, 1.  , 1.25, 2.  ],
-       [ 1.25, 0.5 , 0.25, 0.5 , 1.25],
-       [ 1.  , 0.25, 0.  , 0.25, 1.  ],
-       [ 1.25, 0.5 , 0.25, 0.5 , 1.25],
-       [ 2.  , 1.25, 1.  , 1.25, 2.  ]])
-\end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-    \myemph{\Large 2D data: \texttt{mlab.mesh}}
-    \vspace*{0.25in}
-
-    \emphbar{\PythonCode{In []: mlab.mesh(x, y, z)}}
-
-    \alert{Points needn't be regular}
-
-    \vspace*{0.25in}
-\begin{lstlisting}
-In []: phi, theta = mgrid[0:pi:20j, 
-...                         0:2*pi:20j]
-In []: x = sin(phi)*cos(theta)
-In []: y = sin(phi)*sin(theta)
-In []: z = cos(phi)
-In []: mlab.mesh(x, y, z, 
-...           representation=
-...           'wireframe')
-\end{lstlisting}
-
+from scipy.optimize import fsolve
+  \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
+  \frametitle{from \ldots import in a conventional way!}
+  \small
+  \begin{lstlisting}
+from scipy import linspace, pi, sin
+from pylab import plot, legend, annotate
+from pylab import xlim, ylim
 
-  \begin{columns}
-        \column{0.25\textwidth}
-        \myemph{\Large 3D data}
-        \column{0.5\textwidth}
-        \pgfimage[width=1.5in]{MEDIA/m2/mlab/contour3d}\\        
-    \end{columns}
-\begin{lstlisting}
-In []: x, y, z = mgrid[-5:5:64j, 
-...                -5:5:64j, 
-...                -5:5:64j]
-In []: mlab.contour3d(x*x*0.5 + y*y + 
-                   z*z*2)
-\end{lstlisting}
+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)
+  \end{lstlisting}
 \end{frame}
 
 \begin{frame}[fragile]
-
-    \myemph{\Large 3D vector data: \PythonCode{mlab.quiver3d}}
-    \vspace*{0.25in}
-
-    \pgfimage[width=2in]{MEDIA/m2/mlab/quiver3d_ex}\\
-    
-\begin{lstlisting}
-In []: mlab.test_quiver3d()
-\end{lstlisting}
-
-\emphbar{\PythonCode{obj = mlab.quiver3d(x, y, z, u, v, w)}}
-\inctime{20}
-\end{frame}
-
-
-\subsection{Mayavi2}
-
-\begin{frame}
-  \frametitle{Introduction to Mayavi}
-  \begin{itemize}
-  \item Most scientists not interested in details of visualization
-  \item Visualization of data files with a nice UI
-  \item Interactive visualization of data (think Matlab)
-  \item Embedding visualizations in applications
-  \item Customization
-  \end{itemize}
-  \pause
-  \begin{block}{The Goal}
-      Provide a \alert{flexible} library/app for all of these needs!
-  \end{block}
-\end{frame}
-
-\begin{frame}
-    {Overview of features}
-      \vspace*{-0.3in}
-  \begin{center}    
-    \hspace*{-0.2in}\pgfimage[width=5in]{MEDIA/m2/m2_app3_3}
-  \end{center}    
-\end{frame}
-
-
-\begin{frame}
-    \frametitle{Mayavi in applications}
-      \vspace*{-0.3in}
-  \begin{center}    
-    \hspace*{-0.2in}\pgfimage[width=4.5in]{MEDIA/m2/m2_envisage}
-  \end{center}
-\end{frame}
-
-\begin{frame}
-    \frametitle{Live in your dialogs}
-      \vspace*{0.1in}
-  \begin{center}    
-    \hspace*{-0.2in}\pgfimage[width=2.5in]{MEDIA/m2/mlab_tui}
-  \end{center}
-\end{frame}
-
-\begin{frame}
-    {Exploring the documentation}
-    \begin{center}
-    \pgfimage[width=4in]{MEDIA/m2/m2_ug_doc}
-    \end{center}
-\end{frame}
-
+  \frametitle{from \ldots import in a conventional way!}
+  \small
+  \begin{lstlisting}
+import scipy
+import pylab
 
-\begin{frame}
-  \frametitle{Summary}
-      \begin{itemize}
-          \item \url{http://code.enthought.com/projects/mayavi}
-          \item Uses VTK (\url{www.vtk.org})
-          \item BSD license
-          \item Linux, win32 and Mac OS X
-          \item Highly scriptable
-          \item Embed in Traits UIs (wxPython and PyQt4)
-          \item Envisage Plugins
-          \item Debian/Ubuntu/Fedora
-          \item \alert{Pythonic}
-      \end{itemize}
-    
-      \inctime{10}
-
-\end{frame}
-
-\begin{frame}
-    {Getting hands dirty!}
-
-        \begin{block}{Motivational problem}
-        Atmospheric data of temperature over the surface of the earth.
-        Let temperature ($T$) vary linearly with height ($z$):
-        \begin{center}            
-        $T = 288.15 - 6.5z$
-        \end{center}
-        \end{block}
-\end{frame}
-
-\begin{frame}[fragile]
-    \frametitle{Simple solution}
-
-    \begin{lstlisting}
-lat = linspace(-89, 89, 37)
-lon = linspace(0, 360, 37)
-z = linspace(0, 100, 11)
-    \end{lstlisting}
-\pause
-    \begin{lstlisting}
-x, y, z = mgrid[0:360:37j,-89:89:37j,
-                0:100:11j]
-t = 288.15 - 6.5*z
-mlab.contour3d(x, y, z, t)
-mlab.outline()
-mlab.colorbar()
-    \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-    \frametitle{Exercise: Lorenz equation}
-    \begin{columns}
-        \column{0.25\textwidth}
-        \begin{eqnarray*}
-        \frac{d x}{dt} &=& s (y-x)\\
-        \frac{d y}{d t} &=& rx -y -xz\\
-        \frac{d z}{d t} &=& xy - bz\\
-        \end{eqnarray*}
-        \column{0.25\textwidth}
-        Let $s=10,$
-        $r=28,$ 
-        $b=8./3.$
-    \end{columns}
-    \structure{\Large Region of interest}
-  \begin{lstlisting}
-x, y, z = mgrid[-50:50:20j,-50:50:20j,
-                -10:60:20j]
-  \end{lstlisting}
-\inctime{20}
-
-\end{frame}
-\begin{frame}[fragile]
-    \frametitle{Solution}
-  \begin{lstlisting}
-def lorenz(x,y,z,s=10.,r=28.,b=8./3.):
-    u = s*(y-x)
-    v = r*x-y-x*z
-    w = x*y-b*z
-    return u,v,w
-x,y,z = mgrid [-50:50:20j,-50:50:20j,
-                    -10:60:20j ]
-u,v,w = lorenz( x , y , z )
-# Your plot here
-#
-mlab.show()
-
+x = scipy.linspace(-5*scipy.pi, 5*scipy.pi, 500)
+pylab.plot(x, x, 'b')
+pylab.plot(x, -x, 'b')
+pylab.plot(x, scipy.sin(x), 'g', linewidth=2)
+pylab.plot(x, x*scipy.sin(x), 'r', linewidth=3)
+pylab.legend(['x', '-x', 'sin(x)', 'xsin(x)'])
+pylab.annotate('origin', xy = (0, 0))
+pylab.xlim(-5*scipy.pi, 5*scipy.pi)
+pylab.ylim(-5*scipy.pi, 5*scipy.pi)
   \end{lstlisting}
 \end{frame}
 
 \begin{frame}
-  \frametitle{We have covered:}
+  \frametitle{Modules: Standard library}
   \begin{itemize}
-  \item Need of visualization.
-  \item Using mlab to create 3 D plots.
-  \item Mayavi Toolkit.
+  \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}
+
+\begin{frame}[fragile]
+  \frametitle{Modules of special interest}
+  \begin{description}[matplotlibfor2d]
+    \item[\typ{pylab}] Easy, interactive, 2D plotting
+
+    \item[\typ{scipy}] arrays, statistics, optimization, integration, linear
+            algebra, Fourier transforms, signal and image processing,
+            genetic algorithms, ODE solvers, special functions, and more
+
+    \item[\typ{Mayavi}] Easy, interactive, 3D plotting
+  \end{description}
+\end{frame}
+
+\section{Objects}
+\begin{frame}{Everything is an Object!}
+  \begin{itemize}
+    \item \typ{int}
+    \item \typ{float}
+    \item \typ{str}
+    \item \typ{list}
+    \item \typ{tuple}
+    \item \typ{string}
+    \item \typ{dictionary}
+    \item \typ{function}
+    \item User defined class is also an object!
+  \end{itemize}
+\end {frame}
+
+\begin{frame}[fragile]
+\frametitle{Using Objects}
+  \begin{itemize}
+    \item Creating Objects
+    \begin{itemize}
+      \item Initialization
+    \end{itemize}
+    \begin{lstlisting}
+In []: a = str()
+
+In []: b = "Hello World"
+    \end{lstlisting}
+    \item Object Manipulation
+    \begin{itemize}
+      \item Object methods
+      \item ``.'' operator
+    \end{itemize}
+  \begin{lstlisting}
+In []: "Hello World".split()
+Out[]: ['Hello', 'World']
+    \end{lstlisting}
   \end{itemize}
 \end{frame}
 
-\end{document}
+\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 Functions: Default and Keyword arguments
+    \item Modules
+    \item Objects
+  \end{itemize}
+\end{frame}
+
+\end{document}
\ No newline at end of file
--- a/day2/session4.tex	Fri Nov 06 18:39:56 2009 +0530
+++ b/day2/session4.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -100,7 +100,7 @@
 \author[FOSSEE] {FOSSEE}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {1 November, 2009\\Day 2, Session 3}
+\date[] {8 November, 2009\\Day 2, Session 4}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 %\pgfdeclareimage[height=0.75cm]{iitblogo}{iitblogo}
--- a/day2/session5.tex	Fri Nov 06 18:39:56 2009 +0530
+++ b/day2/session5.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -78,7 +78,7 @@
 \author[FOSSEE] {FOSSEE}
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {1 November, 2009\\Day 2, Session 4}
+\date[] {8 November, 2009\\Day 2, Session 5}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 %\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/day2/session6.tex	Fri Nov 06 18:40:13 2009 +0530
@@ -0,0 +1,558 @@
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Tutorial slides on Python.
+%
+% Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>
+% Copyright (c) 2005-2009, Prabhu Ramachandran
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\documentclass[compress,14pt]{beamer}
+% \documentclass[handout]{beamer}
+% \usepackage{pgfpages}
+% \pgfpagesuselayout{4 on 1}[a4paper,border, shrink=5mm,landscape]
+\usepackage{tikz}
+\newcommand{\hyperlinkmovie}{}
+%\usepackage{movie15}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Note that in presentation mode 
+% \paperwidth  364.19536pt
+% \paperheight 273.14662pt
+% h/w = 0.888
+
+
+\mode<presentation>
+{
+  \usetheme{Warsaw}
+  %\usetheme{Boadilla}
+  %\usetheme{default}
+  \useoutertheme{infolines}
+  \setbeamercovered{transparent}
+}
+
+% To remove navigation symbols
+\setbeamertemplate{navigation symbols}{}
+
+\usepackage{amsmath}
+\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}
+\usepackage{pgf}
+
+\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}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% My Macros
+\setbeamercolor{postit}{bg=yellow,fg=black}
+\setbeamercolor{emphbar}{bg=blue!20, fg=black}
+\newcommand{\emphbar}[1]
+{\begin{beamercolorbox}[rounded=true]{emphbar} 
+      {#1}
+ \end{beamercolorbox}
+}
+%{\centerline{\fcolorbox{gray!50} {blue!10}{
+%\begin{minipage}{0.9\linewidth}
+%    {#1} 
+%\end{minipage}
+%    }}}
+
+\newcommand{\myemph}[1]{\structure{\emph{#1}}}
+\newcommand{\PythonCode}[1]{\lstinline{#1}}
+
+\newcommand{\tvtk}{\texttt{tvtk}}
+\newcommand{\mlab}{\texttt{mlab}}
+
+\newcounter{time}
+\setcounter{time}{0}
+\newcommand{\inctime}[1]{\addtocounter{time}{#1}{\vspace*{0.1in}\tiny \thetime\ m}}
+
+\newcommand\BackgroundPicture[1]{%
+  \setbeamertemplate{background}{%
+      \parbox[c][\paperheight]{\paperwidth}{%
+      \vfill \hfill
+ \hfill \vfill
+}}}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Configuring the theme
+%\setbeamercolor{normal text}{fg=white}
+%\setbeamercolor{background canvas}{bg=black}
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% Title page
+\title[3D Plotting]{3D data Visualization}
+
+\author[FOSSEE] {FOSSEE}
+
+\institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
+\date[] {8 November, 2009\\Day 2, Session 6}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%\pgfdeclareimage[height=0.75cm]{iitblogo}{iitblogo}
+%\logo{\pgfuseimage{iitblogo}}
+
+\AtBeginSection[]
+{
+  \begin{frame}<beamer>
+    \frametitle{Outline}      
+    \tableofcontents[currentsection,currentsubsection]
+  \end{frame}
+}
+
+%% 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}
+}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% 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{3D Data Visualization}
+
+\begin{frame}
+    \frametitle{What is visualization?}
+    \Large
+    \begin{center}
+    Visual representation of data
+    \end{center}
+\end{frame}
+
+
+%% \begin{frame}
+%%     \frametitle{Is this new?}    
+%%     \begin{center}
+%%     We have moved from:
+%%     \end{center}
+%%     \begin{columns}
+%%     \column{}
+%%     \hspace*{-1in}    
+%%     \includegraphics[width=1.75in,height=1.75in, interpolate=true]{data/3832}      
+%%     \column{}\hspace*{-0.25in}
+%%     To
+%%     \column{}
+%%     \hspace*{-1in}
+%%     \includegraphics[width=1.75in, height=1.75in, interpolate=true]{data/torus}  
+%%     \end{columns}
+%% \end{frame}
+
+\begin{frame}
+    \frametitle{3D visualization}
+    \Large
+    \begin{center}
+        Harder but important
+    \end{center}
+\end{frame}
+
+\begin{frame}
+    \frametitle{Is this Graphics?}
+    \Large
+    \begin{center}
+        Visualization is about data!
+    \end{center}
+\end{frame}
+
+\begin{frame}
+    \frametitle{Examples: trajectory in space}
+    \Large
+    \begin{center}
+        \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex}
+    \end{center}
+\end{frame}
+
+\begin{frame}
+    \frametitle{Examples: Fire in a room}
+    \Large
+    \begin{center}
+        Demo of data
+    \end{center}
+\inctime{10}
+\end{frame}
+
+\section{Tools available}
+
+\subsection{mlab}
+
+\begin{frame}
+    {Overview}
+    \Large
+    \begin{itemize}
+        \item Simple
+        \item Convenient
+        \item Full-featured
+    \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+
+    \frametitle{Getting started}
+    \myemph{\Large Vanilla:}
+    \begin{lstlisting}[language=bash]
+        $ ipython -wthread
+    \end{lstlisting}
+    \myemph{\Large with Pylab:}
+    \begin{lstlisting}[language=bash]
+        $ ipython -pylab -wthread
+    \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Using mlab}
+
+    \begin{lstlisting}
+In []:from enthought.mayavi import mlab
+    \end{lstlisting}
+
+    \vspace*{0.5in}
+
+    \myemph{\Large Try these}
+
+    \vspace*{0.25in}
+
+    \begin{lstlisting}
+In []: mlab.test_<TAB>
+In []: mlab.test_contour3d()
+In []: mlab.test_contour3d??
+    \end{lstlisting}
+\end{frame}
+
+\begin{frame}
+    {Exploring the view}
+    \begin{columns}
+        \column{0.6\textwidth}
+    \pgfimage[width=3in]{MEDIA/m2/contour3d}
+        \column{0.4\textwidth}
+        \begin{itemize}
+            \item Mouse
+            \item Keyboard
+            \item Toolbar
+            \item Mayavi icon\pgfimage[width=0.2in]{MEDIA/m2/m2_icon}
+        \end{itemize}
+    \end{columns}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{\mlab\ plotting functions}
+    \begin{columns}
+        \column{0.25\textwidth}
+        \myemph{\Large 0D data}
+        \column{0.5\textwidth}
+    \pgfimage[width=2in]{MEDIA/m2/mlab/points3d_ex}
+    \end{columns}
+
+    \begin{lstlisting}
+In []: t = linspace(0, 2*pi, 50)
+In []: u = cos(t) * pi
+In []: x, y, z = sin(u), cos(u), sin(t)
+    \end{lstlisting}
+    \emphbar{\PythonCode{In []: mlab.points3d(x, y, z)}}
+\end{frame}
+
+\begin{frame}
+  \begin{columns}
+        \column{0.25\textwidth}
+        \myemph{\Large 1D data}
+        \column{0.5\textwidth}
+        \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex}
+  \end{columns}
+  \emphbar{\PythonCode{In []: mlab.plot3d(x, y, z, t)}}
+
+    Plots lines between the points
+    
+\end{frame}
+
+\begin{frame}[fragile]
+    \begin{columns}
+        \column{0.25\textwidth}
+        \myemph{\Large 2D data}
+        \column{0.5\textwidth}
+        \pgfimage[width=2in]{MEDIA/m2/mlab/surf_ex}
+    \end{columns}            
+    \begin{lstlisting}
+In []: x, y = mgrid[-3:3:100j,-3:3:100j]
+In []: z = sin(x*x + y*y)
+    \end{lstlisting}
+
+    \emphbar{\PythonCode{In []: mlab.surf(x, y, z)}}
+
+    \alert{Assumes the points are rectilinear}
+
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{mgrid}
+  \begin{lstlisting}
+In []: mgrid[0:3,0:3]
+Out[]: 
+array([[[0, 0, 0],
+        [1, 1, 1],
+        [2, 2, 2]],
+
+       [[0, 1, 2],
+        [0, 1, 2],
+        [0, 1, 2]]])
+
+In []: mgrid[-1:1:5j]
+Out[]: array([-1., -0.5,  0.,  0.5,  1.])
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Example}
+  \begin{lstlisting}
+In []: x, y = mgrid[-1:1:5j, -1:1:5j]
+In []: z = x*x + y*y
+
+In []: z
+Out[]: 
+array([[ 2.  , 1.25, 1.  , 1.25, 2.  ],
+       [ 1.25, 0.5 , 0.25, 0.5 , 1.25],
+       [ 1.  , 0.25, 0.  , 0.25, 1.  ],
+       [ 1.25, 0.5 , 0.25, 0.5 , 1.25],
+       [ 2.  , 1.25, 1.  , 1.25, 2.  ]])
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+    \myemph{\Large 2D data: \texttt{mlab.mesh}}
+    \vspace*{0.25in}
+
+    \emphbar{\PythonCode{In []: mlab.mesh(x, y, z)}}
+
+    \alert{Points needn't be regular}
+
+    \vspace*{0.25in}
+\begin{lstlisting}
+In []: phi, theta = mgrid[0:pi:20j, 
+...                         0:2*pi:20j]
+In []: x = sin(phi)*cos(theta)
+In []: y = sin(phi)*sin(theta)
+In []: z = cos(phi)
+In []: mlab.mesh(x, y, z, 
+...           representation=
+...           'wireframe')
+\end{lstlisting}
+
+\end{frame}
+
+\begin{frame}[fragile]
+
+  \begin{columns}
+        \column{0.25\textwidth}
+        \myemph{\Large 3D data}
+        \column{0.5\textwidth}
+        \pgfimage[width=1.5in]{MEDIA/m2/mlab/contour3d}\\        
+    \end{columns}
+\begin{lstlisting}
+In []: x, y, z = mgrid[-5:5:64j, 
+...                -5:5:64j, 
+...                -5:5:64j]
+In []: mlab.contour3d(x*x*0.5 + y*y + 
+                   z*z*2)
+\end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+
+    \myemph{\Large 3D vector data: \PythonCode{mlab.quiver3d}}
+    \vspace*{0.25in}
+
+    \pgfimage[width=2in]{MEDIA/m2/mlab/quiver3d_ex}\\
+    
+\begin{lstlisting}
+In []: mlab.test_quiver3d()
+\end{lstlisting}
+
+\emphbar{\PythonCode{obj = mlab.quiver3d(x, y, z, u, v, w)}}
+\inctime{20}
+\end{frame}
+
+
+\subsection{Mayavi2}
+
+\begin{frame}
+  \frametitle{Introduction to Mayavi}
+  \begin{itemize}
+  \item Most scientists not interested in details of visualization
+  \item Visualization of data files with a nice UI
+  \item Interactive visualization of data (think Matlab)
+  \item Embedding visualizations in applications
+  \item Customization
+  \end{itemize}
+  \pause
+  \begin{block}{The Goal}
+      Provide a \alert{flexible} library/app for all of these needs!
+  \end{block}
+\end{frame}
+
+\begin{frame}
+    {Overview of features}
+      \vspace*{-0.3in}
+  \begin{center}    
+    \hspace*{-0.2in}\pgfimage[width=5in]{MEDIA/m2/m2_app3_3}
+  \end{center}    
+\end{frame}
+
+
+\begin{frame}
+    \frametitle{Mayavi in applications}
+      \vspace*{-0.3in}
+  \begin{center}    
+    \hspace*{-0.2in}\pgfimage[width=4.5in]{MEDIA/m2/m2_envisage}
+  \end{center}
+\end{frame}
+
+\begin{frame}
+    \frametitle{Live in your dialogs}
+      \vspace*{0.1in}
+  \begin{center}    
+    \hspace*{-0.2in}\pgfimage[width=2.5in]{MEDIA/m2/mlab_tui}
+  \end{center}
+\end{frame}
+
+\begin{frame}
+    {Exploring the documentation}
+    \begin{center}
+    \pgfimage[width=4in]{MEDIA/m2/m2_ug_doc}
+    \end{center}
+\end{frame}
+
+
+\begin{frame}
+  \frametitle{Summary}
+      \begin{itemize}
+          \item \url{http://code.enthought.com/projects/mayavi}
+          \item Uses VTK (\url{www.vtk.org})
+          \item BSD license
+          \item Linux, win32 and Mac OS X
+          \item Highly scriptable
+          \item Embed in Traits UIs (wxPython and PyQt4)
+          \item Envisage Plugins
+          \item Debian/Ubuntu/Fedora
+          \item \alert{Pythonic}
+      \end{itemize}
+    
+      \inctime{10}
+
+\end{frame}
+
+\begin{frame}
+    {Getting hands dirty!}
+
+        \begin{block}{Motivational problem}
+        Atmospheric data of temperature over the surface of the earth.
+        Let temperature ($T$) vary linearly with height ($z$):
+        \begin{center}            
+        $T = 288.15 - 6.5z$
+        \end{center}
+        \end{block}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Simple solution}
+
+    \begin{lstlisting}
+lat = linspace(-89, 89, 37)
+lon = linspace(0, 360, 37)
+z = linspace(0, 100, 11)
+    \end{lstlisting}
+\pause
+    \begin{lstlisting}
+x, y, z = mgrid[0:360:37j,-89:89:37j,
+                0:100:11j]
+t = 288.15 - 6.5*z
+mlab.contour3d(x, y, z, t)
+mlab.outline()
+mlab.colorbar()
+    \end{lstlisting}
+\end{frame}
+
+\begin{frame}[fragile]
+    \frametitle{Exercise: Lorenz equation}
+    \begin{columns}
+        \column{0.25\textwidth}
+        \begin{eqnarray*}
+        \frac{d x}{dt} &=& s (y-x)\\
+        \frac{d y}{d t} &=& rx -y -xz\\
+        \frac{d z}{d t} &=& xy - bz\\
+        \end{eqnarray*}
+        \column{0.25\textwidth}
+        Let $s=10,$
+        $r=28,$ 
+        $b=8./3.$
+    \end{columns}
+    \structure{\Large Region of interest}
+  \begin{lstlisting}
+x, y, z = mgrid[-50:50:20j,-50:50:20j,
+                -10:60:20j]
+  \end{lstlisting}
+\inctime{20}
+
+\end{frame}
+\begin{frame}[fragile]
+    \frametitle{Solution}
+  \begin{lstlisting}
+def lorenz(x,y,z,s=10.,r=28.,b=8./3.):
+    u = s*(y-x)
+    v = r*x-y-x*z
+    w = x*y-b*z
+    return u,v,w
+x,y,z = mgrid [-50:50:20j,-50:50:20j,
+                    -10:60:20j ]
+u,v,w = lorenz( x , y , z )
+# Your plot here
+#
+mlab.show()
+
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}
+  \frametitle{We have covered:}
+  \begin{itemize}
+  \item Need of visualization.
+  \item Using mlab to create 3 D plots.
+  \item Mayavi Toolkit.
+  \end{itemize}
+\end{frame}
+
+\end{document}
+