124 %%   \frametitle{Outline}

   124 %%   \frametitle{Outline}

   125 %%   \tableofcontents

   125 %%   \tableofcontents

   126 %%   % You might wish to add the option [pausesections]

   126 %%   % You might wish to add the option [pausesections]

   127 %% \end{frame}

   127 %% \end{frame}

   128 

   128 

   129 \begin{frame}

   130 \begin{frame}

   130   \frametitle{More on data processing}

   131   \frametitle{More on data processing}

   131   \begin{block}{}

   132   \begin{block}{}

   132     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?

   133     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?

   133   \end{block}

   134   \end{block}

   176     \item Marks of 5 subjects: English, Hindi, Maths, Science, Social

   177     \item Marks of 5 subjects: English, Hindi, Maths, Science, Social

   177     \item Total marks

   178     \item Total marks

   178     \item Pass/Fail (P/F)

   179     \item Pass/Fail (P/F)

   179     \item Withdrawn (W)

   180     \item Withdrawn (W)

   180   \end{itemize}

   181   \end{itemize}

   183 \begin{frame}[fragile]

   186 \begin{frame}[fragile]

   184   \frametitle{File reading and parsing \ldots}

   187   \frametitle{File reading and parsing \ldots}

   185   \begin{lstlisting}

   188   \begin{lstlisting}

   186 for record in open('sslc1.txt'):

   189 for record in open('sslc1.txt'):

   187     fields = record.split(';')

   190     fields = record.split(';')

   188   \end{lstlisting}

   191   \end{lstlisting}

   189 \end{frame}

   192 \end{frame}

   190 

   193 

   191 \begin{frame}[fragile]

   195 \begin{frame}[fragile]

   192   \frametitle{Dictionary: Introduction}

   196   \frametitle{Dictionary: Introduction}

   193   \begin{itemize}

   197   \begin{itemize}

   194     \item lists index: 0 \ldots n

   198     \item lists index: 0 \ldots n

   195     \item dictionaries index using strings

   199     \item dictionaries index using strings

   196   \end{itemize}

   200   \end{itemize}

   198 d = \{ ``Hitchhiker's guide'' : 42,

   202 d = \{ ``Hitchhiker's guide'' : 42,

   199      ``Terminator'' : ``I'll be back''\}\\

   203      ``Terminator'' : ``I'll be back''\}\\

   200 d[``Terminator''] => ``I'll be back''

   204 d[``Terminator''] => ``I'll be back''

   202 \end{frame}

   206 \end{frame}

   203 

   207 

   204 \begin{frame}[fragile]

   208 \begin{frame}[fragile]

   205   \frametitle{Dictionary: Introduction}

   209   \frametitle{Dictionary: Introduction}

   207 In [1]: d = {"Hitchhiker's guide" : 42,

   211 In [1]: d = {"Hitchhiker's guide" : 42,

   208       "Terminator" : "I'll be back"}

   212       "Terminator" : "I'll be back"}

   209 

   213 

   210 In [2]: d["Hitchhiker's guide"]

   214 In [2]: d["Hitchhiker's guide"]

   211 Out[2]: 42

   215 Out[2]: 42

   213 In [3]: "Hitchhiker's guide" in d

   217 In [3]: "Hitchhiker's guide" in d

   214 Out[3]: True

   218 Out[3]: True

   215 

   219 

   216 In [4]: "Guido" in d

   220 In [4]: "Guido" in d

   217 Out[4]: False

   221 Out[4]: False

   219 \end{frame}

   223 \end{frame}

   220 

   224 

   221 \begin{frame}[fragile]

   225 \begin{frame}[fragile]

   222   \frametitle{Dictionary: Introduction}

   226   \frametitle{Dictionary: Introduction}

   224 In [5]: d.keys()

   228 In [5]: d.keys()

   225 Out[5]: ['Terminator', "Hitchhiker's 

   229 Out[5]: ['Terminator', "Hitchhiker's 

   226                               guide"]

   230                               guide"]

   227 

   231 

   228 In [6]: d.values()

   232 In [6]: d.values()

   229 Out[6]: ["I'll be back", 42]

   233 Out[6]: ["I'll be back", 42]

   231 \end{frame}

   235 \end{frame}

   232 

   236 

   233 \begin{frame}[fragile]

   237 \begin{frame}[fragile]

   234   \frametitle{enumerate: Iterating through list indices}

   238   \frametitle{enumerate: Iterating through list indices}

   236 In [1]: names = ["Guido","Alex", "Tim"]

   240 In [1]: names = ["Guido","Alex", "Tim"]

   237 

   241 

   238 In [2]: for i, name in enumerate(names):

   242 In [2]: for i, name in enumerate(names):

   239    ...:     print i, name

   243    ...:     print i, name

   240    ...: 

   244    ...: 

   241 0 Guido

   245 0 Guido

   242 1 Alex

   246 1 Alex

   243 2 Tim

   247 2 Tim

   245 \end{frame}

   250 \end{frame}

   246 

   251 

   247 \begin{frame}[fragile]

   252 \begin{frame}[fragile]

   248   \frametitle{Dictionary: Building parsed data}

   253   \frametitle{Dictionary: Building parsed data}

   251 science = {} # is an empty dictionary

   256 science = {} # is an empty dictionary

   253 \end{frame}

   258 \end{frame}

   254 

   259 

   255 \begin{frame}[fragile]

   260 \begin{frame}[fragile]

   256   \frametitle{Dictionary - Building parsed data}

   261   \frametitle{Dictionary - Building parsed data}

   257   \begin{itemize}

   262   \begin{itemize}

   289 if score > 90:

   294 if score > 90:

   290     science[region_code] += 1

   295     science[region_code] += 1

   291   \end{lstlisting}

   296   \end{lstlisting}

   292 \end{frame}

   297 \end{frame}

   293 

   298 

   294 \begin{frame}[fragile]

   300 \begin{frame}[fragile]

   295   \frametitle{Pie charts}

   301   \frametitle{Pie charts}

   296   \small

   302   \small

   297   \begin{lstlisting}

   303   \begin{lstlisting}

   298 figure(1)

   304 figure(1)

   306     \column{5.25\textwidth}

   312     \column{5.25\textwidth}

   307     \hspace*{1.1in}

   313     \hspace*{1.1in}

   308 \includegraphics[height=2in, interpolate=true]{data/science}

   314 \includegraphics[height=2in, interpolate=true]{data/science}

   309     \column{0.8\textwidth}

   315     \column{0.8\textwidth}

   310 \end{columns}

   316 \end{columns}

   311 \end{frame}

   318 \end{frame}

   312 

   319 

   313 \begin{frame}[fragile]

   320 \begin{frame}[fragile]

   314   \frametitle{Building data for all subjects \ldots}

   321   \frametitle{Building data for all subjects \ldots}

   315   \begin{lstlisting}

   322   \begin{lstlisting}

   379 \begin{frame}[fragile]

   386 \begin{frame}[fragile]

   380   \frametitle{Pie charts}

   387   \frametitle{Pie charts}

   381   \includegraphics[height=3in, interpolate=true]{data/all_regions}

   388   \includegraphics[height=3in, interpolate=true]{data/all_regions}

   382 \end{frame}

   389 \end{frame}

   383 

   390 

   384 \begin{frame}[fragile]

   392 \begin{frame}[fragile]

   385   \frametitle{Obtaining statistics}

   393   \frametitle{Obtaining statistics}

   386   \begin{lstlisting}

   394   \begin{lstlisting}

   387 math_scores = array(scores[2])

   395 math_scores = array(scores[2])

   388 

   396 

   393 print "Mode: ", stats.mode(math_scores)

   401 print "Mode: ", stats.mode(math_scores)

   394 

   402 

   395 print "Standard Deviation: ",

   403 print "Standard Deviation: ",

   396               std(math_scores)

   404               std(math_scores)

   397   \end{lstlisting}

   405   \end{lstlisting}

   398 \end{frame}

   407 \end{frame}

   399 

   408 

   400 \begin{frame}[fragile]

   409 \begin{frame}[fragile]

   401   \frametitle{What tools did we use?}

   410   \frametitle{What tools did we use?}

   402   \begin{itemize}

   411   \begin{itemize}