Workshop materials: comparison day1/Session-4.tex

equal deleted inserted replaced

-:fccb3551c7d5
+:fc74987a475d
 \title[Basic Python]{Python:\\Advanced Python data structures, Functions and Debugging}
 \author[FOSSEE Team] {Asokan Pichai\\Prabhu Ramachandran}
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
-\date[] {10, October 2009}
+\date[] {10, October 2009\\Day 1, Session 4}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
 %\logo{\pgfuseimage{iitmlogo}}
 \begin{frame}[fragile]
 \frametitle{Functions: default arguments}
 \small
 \begin{lstlisting}
-def ask_ok(prompt, retries=4,
+def ask_ok(prompt, complaint='Yes or no!'):
-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
-retries = retries - 1
-if retries < 0:
-raise IOError, 'bad user'
 print complaint
+ask_ok('?')
+ask_ok('?', '[Y/N]')
 \end{lstlisting}
 \end{frame}
 \begin{frame}[fragile]
 \frametitle{Functions: keyword arguments}
 \small
 \begin{lstlisting}
-def parrot(voltage, state='a stiff',
+def ask_ok(prompt, complaint='Yes or no!'):
-action='voom', type='Royal Blue'):
+while True:
-print "-- This parrot wouldn't", action,
+ok = raw_input(prompt)
-print "if you supply", voltage, "Volts."
+if ok in ('y', 'ye', 'yes'):
-print "-- Lovely plumage, the", type
+return True
-print "-- It's", state, "!"
+if ok in ('n', 'no', 'nop',
+'nope'):
-parrot(1000)
+return False
-parrot(action = 'VOOOOOM', voltage = 1000000)
+print complaint
-parrot('a thousand',
-state = 'pushing up the daisies')
+ask_ok(prompt='?')
-parrot('a million', 'bereft of life', 'jump')
+ask_ok(prompt='?', complaint='[Y/N]')
-\end{lstlisting}
+ask_ok(complaint='[Y/N]', prompt='?')
-\end{frame}
+\end{lstlisting}
+\inctime{15}
-\begin{frame}[fragile]
-\frametitle{Functions: arbitrary argument lists}
-\begin{itemize}
-\item Arbitrary number of arguments using \verb+*args+ or
-\verb+*whatever+
-\item Keyword arguments using \verb+**kw+
-\item Given a tuple/dict how do you call a function?
-\begin{itemize}
-\item Using argument unpacking
-\item For positional arguments: \verb+foo(*[5, 10])+
-\item For keyword args: \verb+foo(**{'a':5, 'b':10})+
-\end{itemize}
-\end{itemize}
-\end{frame}
-\begin{frame}[fragile]
-\begin{lstlisting}
-def foo(a=10, b=100):
-print a, b
-def func(*args, **keyword):
-print args, keyword
-# Unpacking:
-args = [5, 10]
-foo(*args)
-kw = {'a':5, 'b':10}
-foo(**kw)
-\end{lstlisting}
-\inctime{15}
 \end{frame}
 \subsection{Functional programming}
 \begin{frame}[fragile]
 \frametitle{Functional programming}
 What is the basic idea?\\
 Why is it interesting?\\
 \typ{map, reduce, filter}\\
 list comprehension\\
 generators
-\inctime{15}
+\end{frame}
-\end{frame}
+\begin{frame}[fragile]
+\frametitle{List Comprehensions}
+Lets say we want to squares of all the numbers from 1 to 100
+\begin{lstlisting}
+squares = []
+for i in range(1, 100):
+squares.append(i * i)
+\end{lstlisting}
+\begin{lstlisting}
+# list comprehension
+squares = [i*i for i in range(1, 100)]
+\end{lstlisting}
+Which is more readable?
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{List Comprehensions}
+What if you had a more complex function?
+Lets say we want squares of numbers from 1 to 100 ending in 1, 2, 5, 7 only
+\begin{lstlisting}
+squares = []
+for i in range(1, 100):
+if i % 10 in [1, 2, 5, 7]:
+squares.append(i * i)
+\end{lstlisting}
+\begin{lstlisting}
+# list comprehension
+squares = [i*i for i in range(1, 100)
+if i % 10 in [1, 2, 5, 7]]
+\end{lstlisting}
+Which is more readable?
+\inctime{15}
+\end{frame}
 \subsection{Debugging}
 \begin{frame}[fragile]
 \frametitle{Errors}
 \begin{lstlisting}
 \begin{itemize}
 \item  \kwrd{print} based strategy
 \item Process: Hypothesis, test, refine, rinse-repeat
 \item Using \typ{\%debug} and \typ{\%pdb} in IPython
 \end{itemize}
-\inctime{15}
 \end{frame}
 \begin{frame}[fragile]
 \frametitle{Debugging: example}
 \small
 NameError: global name 'spam' is not defined
 > /media/python/iitb/workshops/day1/mymodule.py(2)test()
 0     print spam
 ipdb>
 \end{lstlisting}
+\inctime{15}
 \end{frame}
 \begin{frame}[fragile]
 \frametitle{Debugging: Exercise}
-\end{frame}
+\inctime{10}
+\end{frame}
+\begin{frame}
+\frametitle{What did we learn?}
+\begin{itemize}
+\item Creating and using Dictionaries
+\item Creating and using Sets
+\item Advances Functions: default arguments, keyword arguments
+\item Functional Programming, list comprehensions
+\item Errors and Exceptions in Python
+\item Debugging: How to use pdb, \%pdb and \%debug in IPython
+\end{itemize}
+\end{frame}
 \end{document}

changeset 53	fc74987a475d
parent 50	aabaf8ec0a08
child 54	c3fe152b3539