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\section{Tuples}
\begin{frame}[fragile]
\frametitle{Tuples -- Initialization}
\begin{lstlisting}
In[]: t = (1, 2.5, "hello", -4, "world", 1.24, 5)
In[]: t
\end{lstlisting}
\begin{itemize}
\item It is not always necessary to use parenthesis
\end{itemize}
\begin{lstlisting}
In[]: a = 1, 2, 3
In[]: b = 1,
\end{lstlisting}
\end{frame}
\begin{frame}[fragile]
\frametitle{Indexing}
\begin{lstlisting}
In[]: t[3]
In[]: t[1:5:2]
In[]: t[2] = "Hello"
\end{lstlisting}
\begin{itemize}
\item \alert{Tuples are immutable!}
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Swapping values}
\begin{lstlisting}
In[]: a = 5
In[]: b = 7
In[]: temp = a
In[]: a = b
In[]: b = temp
\end{lstlisting}
\begin{itemize}
\item Here's the Pythonic way of doing it
\end{itemize}
\begin{lstlisting}
In[]: a, b = b, a
\end{lstlisting}
\begin{itemize}
\item The variables can be of different data-types
\end{itemize}
\begin{lstlisting}
In[]: a = 2.5
In[]: b = "hello"
In[]: a, b = b, a
\end{lstlisting}
\end{frame}
\begin{frame}[fragile]
\frametitle{Tuple packing \& unpacking}
\begin{lstlisting}
In[]: 5,
In[]: 5, "hello", 2.5
\end{lstlisting}
\begin{itemize}
\item Tuple packing and unpacking, when swapping
\end{itemize}
\begin{lstlisting}
In[]: a, b = b, a
\end{lstlisting}
\end{frame}
\section{Dictionaries}
\begin{frame}[fragile]
\frametitle{Creating Dictionaries}
\begin{lstlisting}
In[]: mt_dict = {}
In[]: extensions = {'jpg' : 'JPEG Image',
'py' : 'Python script',
'html' : 'Html document',
'pdf' : 'Portable Document Format'}
In[]: extensions
\end{lstlisting}
\begin{itemize}
\item Key-Value pairs
\item \alert{ No ordering of keys! }
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Accessing Elements}
\begin{lstlisting}
In[]: print extensions['jpg']
\end{lstlisting}
\begin{itemize}
\item Values can be accessed using keys
\end{itemize}
\begin{lstlisting}
In[]: print extensions['zip']
\end{lstlisting}
\begin{itemize}
\item Values of non-existent keys cannot, obviously, be accessed
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Adding \& Removing Elements}
\begin{itemize}
\item Adding a new key-value pair
\end{itemize}
\begin{lstlisting}
In[]: extensions['cpp'] = 'C++ code'
In[]: extensions
\end{lstlisting}
\begin{itemize}
\item Deleting a key-value pair
\end{itemize}
\begin{lstlisting}
In[]: del extension['pdf']
In[]: extensions
\end{lstlisting}
\begin{itemize}
\item Assigning to existing key, modifies the value
\end{itemize}
\begin{lstlisting}
In[]: extensions['cpp'] = 'C++ source code'
In[]: extensions
\end{lstlisting}
\end{frame}
\begin{frame}[fragile]
\frametitle{Containership}
\begin{lstlisting}
In[]: 'py' in extensions
In[]: 'odt' in extensions
\end{lstlisting}
\begin{itemize}
\item Allow checking for container-ship of keys; NOT values
\item Use the \texttt{in} keyword to check for container-ship
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Lists of Keys and Values}
\begin{lstlisting}
In[]: extensions.keys()
In[]: extensions.values()
\end{lstlisting}
\begin{itemize}
\item Note that the order of the keys and values match
\item That can be relied upon and used
\end{itemize}
\begin{lstlisting}
In[]: for each in extensions.keys():
....: print each, "-->", extensions[each]
....:
\end{lstlisting}
\end{frame}
\section{Sets}
\begin{frame}[fragile]
\frametitle{Creating Sets}
\begin{lstlisting}
In[]: a_list = [1, 2, 1, 4, 5, 6, 2]
In[]: a = set(a_list)
In[]: a
\end{lstlisting}
\begin{itemize}
\item Conceptually identical to the sets in mathematics
\item Duplicate elements not allowed
\item No ordering of elements exists
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Operations on Sets}
\begin{lstlisting}
In[]: f10 = set([1, 2, 3, 5, 8])
In[]: p10 = set([2, 3, 5, 7])
\end{lstlisting}
\begin{itemize}
\item Mathematical operations performed on sets, can be performed
\end{itemize}
\begin{itemize}
\item Union
\begin{lstlisting}
In[]: f10 | p10
\end{lstlisting}
\item Intersection
\begin{lstlisting}
In[]: f10 & p10
\end{lstlisting}
\item Difference
\begin{lstlisting}
In[]: f10 - p10
\end{lstlisting}
\item Symmetric Difference
\begin{lstlisting}
In[]: f10 ^ p10
\end{lstlisting}
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Sub-sets}
\begin{itemize}
\item Proper Subset
\begin{lstlisting}
In[]: b = set([1, 2])
In[]: b < f10
\end{lstlisting}
\item Subsets
\begin{lstlisting}
In[]: f10 <= f10
\end{lstlisting}
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Elements of sets}
\begin{itemize}
\item Containership
\begin{lstlisting}
In[]: 1 in f10
In[]: 4 in f10
\end{lstlisting}
\item Iterating over elements
\begin{lstlisting}
In[]: for i in f10:
....: print i,
....:
\end{lstlisting}
\item Subsets
\begin{lstlisting}
In[]: f10 <= f10
\end{lstlisting}
\end{itemize}
\end{frame}
\begin{frame}[fragile]
\frametitle{Sets -- Example}
\begin{block}{}
Given a list of marks, \texttt{[20, 23, 22, 23, 20, 21, 23]} list
all the duplicates
\end{block}
\begin{lstlisting}
In[]: marks = [20, 23, 22, 23, 20, 21, 23]
In[]: marks_set = set(marks)
In[]: for mark in marks_set:
....: marks.remove(mark)
# left with only duplicates
In[]: duplicates = set(marks)
\end{lstlisting}
\end{frame}
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