day2/cheatsheet1.tex
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     1 \documentclass[12pt]{article}
       
     2 
       
     3 
       
     4 \title{Python: Basics}
       
     5 \author{FOSSEE}
       
     6 \usepackage{listings}
       
     7 \lstset{language=Python,
       
     8     basicstyle=\ttfamily,
       
     9 commentstyle=\itshape\bfseries, 
       
    10 showstringspaces=false
       
    11 }
       
    12 \newcommand{\typ}[1]{\lstinline{#1}}
       
    13 \usepackage[english]{babel}
       
    14 \usepackage[latin1]{inputenc}
       
    15 \usepackage{times}
       
    16 \usepackage[T1]{fontenc}
       
    17 \usepackage{ae,aecompl}
       
    18 \usepackage{mathpazo,courier,euler}
       
    19 \usepackage[scaled=.95]{helvet}
       
    20 
       
    21 \begin{document}
       
    22 \date{}
       
    23 \vspace{-1in}
       
    24 \begin{center}
       
    25 \LARGE{Python: Basics}\\
       
    26 \large{FOSSEE}
       
    27 \end{center}
       
    28 \section{Data types}
       
    29 Complex Numbers
       
    30 \begin{lstlisting}
       
    31 In []: c = 3+4j
       
    32 In []: abs(c)
       
    33 Out[]: 5.0
       
    34 In []: c.imag
       
    35 Out[]: 4.0
       
    36 In []: c.real
       
    37 Out[]: 3.0
       
    38 \end{lstlisting}
       
    39 Boolean
       
    40 \begin{lstlisting}     
       
    41 In []: a = False
       
    42 In []: b = True
       
    43 In []: c = True
       
    44 In []: (a and b) or c
       
    45 Out[]: True
       
    46 \end{lstlisting}
       
    47 Strings
       
    48   \begin{lstlisting}
       
    49 In []: w = "hello"
       
    50 In []: print w[0] + w[2] + w[-1]
       
    51 Out[]: hlo
       
    52 In []: len(w)
       
    53 Out[]: 5
       
    54 In []: w[0] = 'H' # ERROR: Strings are immutable 
       
    55   \end{lstlisting}
       
    56 String methods
       
    57   \begin{lstlisting}
       
    58 In []: a = 'Hello World' 
       
    59 In []: a.startswith('Hell') # 'a' starts with 'Hell'
       
    60 In []: a.endswith('ld') # 'a' ends with 'ld'
       
    61 In []: a.upper() # all characters to upper case
       
    62 In []: a.lower() # all characters to lower case
       
    63 In []: ''.join(['a', 'b', 'c'])
       
    64 Out[]: 'abc'
       
    65   \end{lstlisting}
       
    66 String formatting
       
    67   \begin{lstlisting}
       
    68 In []: x, y = 1, 1.234
       
    69 In []: 'x is %s, y is %s' %(x, y)
       
    70 Out[]: 'x is 1, y is 1.234'
       
    71   \end{lstlisting}
       
    72 Arithmetic Operators
       
    73   \begin{lstlisting}
       
    74 In []: 45 % 2 # Modulo operator
       
    75 Out[]: 1
       
    76 In []: 1234567891234567890 ** 3 # Power
       
    77 In []: a = 5
       
    78 In []: a += 1
       
    79 In []: a *= 2
       
    80   \end{lstlisting}
       
    81 String Operations
       
    82 \begin{lstlisting}
       
    83 In []: s = 'Hello'
       
    84 In []: p = 'World'
       
    85 In []: s + p 
       
    86 Out[]: 'HelloWorld'
       
    87 In []: s * 4
       
    88 Out[]: 'HelloHelloHelloHello'
       
    89 \end{lstlisting}
       
    90 Relational and Logical Operators
       
    91 \begin{lstlisting}
       
    92 In []: p, z, n = 1, 0, -1
       
    93 In []: p == n
       
    94 Out[]: False
       
    95 In []: p >= n
       
    96 Out[]: True
       
    97 In []: n < z < p
       
    98 Out[]: True
       
    99 In []: p + n != z
       
   100 Out[]: False
       
   101 \end{lstlisting}
       
   102 Built-ins
       
   103 \begin{lstlisting}
       
   104 In []: int(17 / 2.0)
       
   105 Out[]: 8
       
   106 In []: float(17 / 2)
       
   107 Out[]: 8.0
       
   108 In []: str(17 / 2.0)
       
   109 Out[]: '8.5'
       
   110 In []: round( 7.5 )
       
   111 Out[]: 8.0
       
   112 \end{lstlisting}
       
   113 Console Input
       
   114 \begin{lstlisting}
       
   115 In []: a = raw_input('Enter a value: ')
       
   116 Enter a value: 5
       
   117 \end{lstlisting}
       
   118 \section{Conditionals}
       
   119 \typ{if}
       
   120 \begin{lstlisting}
       
   121 In []: x = int(raw_input("Enter an integer:"))
       
   122 In []: if x < 0:
       
   123   ...:     print 'Be positive!'
       
   124   ...: elif x == 0:
       
   125   ...:     print 'Zero'
       
   126   ...: elif x == 1:
       
   127   ...:     print 'Single'
       
   128   ...: else:
       
   129   ...:     print 'More'
       
   130 \end{lstlisting}
       
   131 Ternary Operator
       
   132 \begin{lstlisting}
       
   133 In []: a = raw_input('Enter number(Q to quit):')
       
   134 In []: num = int(a) if a != 'Q' else 0
       
   135 \end{lstlisting}
       
   136 \end{document}