Objective Questions
-------------------

.. A mininum of 8 questions here. 

1. ``loadtxt`` can read data only from a file with one column
   only. True or False?

   Answer: False

#. To read a file with multiple columns, into separate simple
   sequences, ``loadtxt`` is given the additional argument ______?

   Answer: ``unpack=True``

#. We have a file with two columns of data separated by one of the
   following characters. Which of them doesn't require the delimiter
   argument to be specified, when using ``loadtxt``. 

   a. ;
   #. , 
   #. :
   #. [space] 
   
   Answer: [space]
   
#. Given a file ``data.txt`` with three columns of data separated by
   spaces, read it into one complex sequence. 

   Answer: ``x = loadtxt("data.txt")``

#. Given a file ``data.txt`` with three columns of data separated by
   spaces, read it into 3 separate simple sequences. 

   Answer: ``x = loadtxt("data.txt", unpack=True)``

#. Given a file ``data.txt`` with three columns of data separated by
   ``:``, read it into one complex sequence. 

   Answer: ``x = loadtxt("data.txt", delimiter=":")``

#. Given a file ``data.txt`` with three columns of data separated by
   ":", read it into 3 separate simple sequences. 

   Answer: ``x = loadtxt("data.txt", unpack=True, delimiter=":")``

#. To use the loadtxt command, each row should have the same number of
   values, T or F ?

   Answer: True

Larger Questions
----------------

.. A minimum of 2 questions here. 

1. What will happen if one of the cells is empty?

#. Given a file with 3 columns of data but two different delimiters,
   what do you think will happen?

#. Read a column with text? 

#. An input file contains 5 columns of data. Use only the second and fourth
   columns of data and load into two different variables.
   [hint: read the documentation, use the argument ``usecols``]