1 Objective Questions

     2 -------------------

     3 

     4  1. How do you split the string "Guido;Rossum;Python" to get the words

     5 

     6    Answer: line.split(';')

     7 

     8  2. line.split() and line.split(' ') are same

     9 

    10    a. True

    11    #. False

    12 

    13    Answer: False

    14 

    15  3. What is the output of the following code::

    16 

    17       line = "Hello;;;World;;"

    18       sub_strs = line.split()

    19       print len(sub_strs)

    20 

    21     Answer: 5

    22 

    23  4. What is the output of "      Hello    World    ".strip()

    24 

    25    a. "Hello World"

    26    #. "Hello     World"

    27    #. "      Hello World"

    28    #. "Hello World     "

    29    

    30    Answer: "Hello    World"

    31 

    32  5. What does "It is a cold night".strip("It") produce

    33     Hint: Read the documentation of strip

    34 

    35    a. "is a cold night"

    36    #. " is a cold nigh" 

    37    #. "It is a cold nigh"

    38    #. "is a cold nigh"

    39 

    40    Answer: " is a cold nigh"

    41 

    42  6. What does int("20") produce

    43 

    44    a. "20"

    45    #. 20.0

    46    #. 20

    47    #. Error

    48 

    49    Answer: 20

    50 

    51  7. What does int("20.0") produce

    52 

    53    a. 20

    54    #. 20.0

    55    #. Error

    56    #. "20"

    57 

    58    Answer: Error

    59 

    60  8. What is the value of float(3/2)

    61 

    62    a. 1.0

    63    #. 1.5

    64    #. 1

    65    #. Error

    66 

    67    Answer: 1.0

    68 

    69  9. what doess float("3/2") produce

    70 

    71    a. 1.0

    72    #. 1.5

    73    #. 1

    74    #. Error

    75 

    76    Answer: Error

    77    

    78  10. See if there is a function available in pylab to calculate the mean

    79      Hint: Use tab completion

    80 

    81 Larger Questions

    82 ================

    83 

    84  1. The file ``pos.txt`` contains two columns of data. The first and second

    85     columns are the x and y co-ordiantes of a particle in motion, respectively.

    86     Plot the trajectory of the particle.

    87 

    88    Answer::

    89 

    90      x_values = []

    91      y_values = []

    92 

    93      for line in open("/home/fossee/pos.txt");

    94          x_str, y_str = line.split()

    95          x = int(x_str)

    96          y = int(y_str)

    97 

    98          x_values.append(x)

    99          y_values.append(y)

   100 

   101          plot(x, y, 'b.')

   102