day2/cheatsheet1.tex
author Santosh G. Vattam <vattam.santosh@gmail.com>
Wed, 11 Nov 2009 12:26:07 +0530
changeset 301 49bdffe4dca5
child 321 8bf99f747817
permissions -rwxr-xr-x
Updated session 2 slides of day 1 and added cheatsheets of day 2.

\documentclass[12pt]{article}


\title{Python: Basics}
\author{FOSSEE}
\usepackage{listings}
\lstset{language=Python,
    basicstyle=\ttfamily,
commentstyle=\itshape\bfseries, 
showstringspaces=false
}
\newcommand{\typ}[1]{\lstinline{#1}}
\usepackage[english]{babel}
\usepackage[latin1]{inputenc}
\usepackage{times}
\usepackage[T1]{fontenc}
\usepackage{ae,aecompl}
\usepackage{mathpazo,courier,euler}
\usepackage[scaled=.95]{helvet}

\begin{document}
\date{}
\vspace{-1in}
\begin{center}
\LARGE{Python: Basics}\\
\large{FOSSEE}
\end{center}
\section{Data types}
Complex Numbers
\begin{lstlisting}
In []: c = 3+4j
In []: abs(c)
Out[]: 5.0
In []: c.imag
Out[]: 4.0
In []: c.real
Out[]: 3.0
\end{lstlisting}
Boolean
\begin{lstlisting}     
In []: a = False
In []: b = True
In []: c = True
In []: (a and b) or c
Out[]: True
\end{lstlisting}
Strings
  \begin{lstlisting}
In []: w = "hello"
In []: print w[0] + w[2] + w[-1]
Out[]: hlo
In []: len(w)
Out[]: 5
In []: w[0] = 'H' # ERROR: Strings are immutable 
  \end{lstlisting}
String methods
  \begin{lstlisting}
In []: a = 'Hello World' 
In []: a.startswith('Hell') # 'a' starts with 'Hell'
In []: a.endswith('ld') # 'a' ends with 'ld'
In []: a.upper() # all characters to upper case
In []: a.lower() # all characters to lower case
In []: ''.join(['a', 'b', 'c'])
Out[]: 'abc'
  \end{lstlisting}
String formatting
  \begin{lstlisting}
In []: x, y = 1, 1.234
In []: 'x is %s, y is %s' %(x, y)
Out[]: 'x is 1, y is 1.234'
  \end{lstlisting}
Arithmetic Operators
  \begin{lstlisting}
In []: 45 % 2 # Modulo operator
Out[]: 1
In []: 1234567891234567890 ** 3 # Power
In []: a = 5
In []: a += 1
In []: a *= 2
  \end{lstlisting}
String Operations
\begin{lstlisting}
In []: s = 'Hello'
In []: p = 'World'
In []: s + p 
Out[]: 'HelloWorld'
In []: s * 4
Out[]: 'HelloHelloHelloHello'
\end{lstlisting}
Relational and Logical Operators
\begin{lstlisting}
In []: p, z, n = 1, 0, -1
In []: p == n
Out[]: False
In []: p >= n
Out[]: True
In []: n < z < p
Out[]: True
In []: p + n != z
Out[]: False
\end{lstlisting}
Built-ins
\begin{lstlisting}
In []: int(17 / 2.0)
Out[]: 8
In []: float(17 / 2)
Out[]: 8.0
In []: str(17 / 2.0)
Out[]: '8.5'
In []: round( 7.5 )
Out[]: 8.0
\end{lstlisting}
Console Input
\begin{lstlisting}
In []: a = raw_input('Enter a value: ')
Enter a value: 5
\end{lstlisting}
\section{Conditionals}
\typ{if}
\begin{lstlisting}
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}
Ternary Operator
\begin{lstlisting}
In []: a = raw_input('Enter number(Q to quit):')
In []: num = int(a) if a != 'Q' else 0
\end{lstlisting}
\end{document}