savefig/questions.rst
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     1 Objective Questions
       
     2 -------------------
       
     3 
       
     4 .. A mininum of 8 questions here (along with answers)
       
     5 
       
     6 
       
     7 1. What argument can be used with savefig to increase the resolution
       
     8    of the plot while saving a plot.
       
     9 
       
    10    a. fname
       
    11    #. transparency
       
    12    #. dpi
       
    13    #. format
       
    14 
       
    15 Answer: dpi
       
    16 
       
    17 2. The fname argument of savefig has to be always absolute path.
       
    18 
       
    19    a. True
       
    20    #. False
       
    21 
       
    22 Answer: False
       
    23 
       
    24 3. You are right now in the directory `/home/fossee`, from the
       
    25    following which one is the correct one in-order to save the plot as
       
    26    svg with the filename `plot` to the directory `/home/fossee/sine/`
       
    27 
       
    28    a. savefig('/sine/plot.svg')
       
    29    #. savefig('sine/plot.svg')
       
    30    #. savefig('home/fossee/sine/plot.svg')
       
    31    #. All of these
       
    32    #. None of the above
       
    33 
       
    34 Answer: savefig('sine/plot.svg')
       
    35 
       
    36 4. Which is the best image format to be used with Latex documents
       
    37    which savefig supports?
       
    38 
       
    39    a. SVG - Scalable Vector Graphics
       
    40    #. EPS - Encapsulated Post Script
       
    41    #. PS - Post Script
       
    42    #. PNG - Portable Network Graphics
       
    43    #. None of the above
       
    44 
       
    45 Answer: EPS - Encapsulated Post Script
       
    46 
       
    47 5. ``savefig('sine.png')`` saves the plot in,
       
    48 
       
    49    a. The root directory ``/`` (on GNU/Linux, Unix based systems)
       
    50       ``c:\`` (on windows).
       
    51    #. Will result in an error as full path is not supplied.
       
    52    #. The current working directory.
       
    53    #. Predefined directory like ``/documents``.
       
    54 
       
    55 Answer: The current working directory.
       
    56 
       
    57 6. Study the following code and tell what will happen,
       
    58    ::
       
    59       savefig('cosine.png',facecolor='blue')
       
    60 
       
    61    a. Will generate an error as plot statements are missing
       
    62    #. Will generate an error as full path is not specified
       
    63    #. Create a file ``cosine.png`` with blue background at the current
       
    64       working directory.
       
    65    #. Create a file ``cosine.png`` with blue background at a
       
    66       predefined directory like ``/documents``.
       
    67 
       
    68 Answer: Create a file ``cosine.png`` with blue background at the
       
    69 	current working directory.
       
    70 
       
    71 7. How to save the below plot as ``sine_green_border.png`` with green
       
    72    color border/edge in the current working directory.  The plot is given
       
    73    as,
       
    74    ::
       
    75 	x = linspace(-5*pi,5*pi,200)
       
    76 	plot(x,sin(x),linewidth=2)
       
    77 	legend(['sin(x)'])
       
    78 
       
    79    a. ``savefig('sine_green_border.png',bordercolor='green')``
       
    80    #. ``savefig('sine_green_border.png',facecolor='green')``
       
    81    #. ``savefig('sine_green_border.png',edgecolor='green')``
       
    82    #. ``savefig('/sine_green_border.png',bordercolor='green')``
       
    83 
       
    84 Answer: savefig('sine_green_border.png',edgecolor='green')
       
    85 
       
    86 8. Given the below code snippet, what does it do?
       
    87    ::
       
    88 	x = linspace(-5*pi,5*pi,200)
       
    89 	plot(x,sin(x),linewidth=2)
       
    90 	legend(['sin(x)'])
       
    91     	savefig('sine.png',format='pdf',papertype='a4')
       
    92 
       
    93    a. Save the sine plot in file sine.png as a pdf file in page-size
       
    94       A4 and saves it into the current working directory
       
    95    #. Save the sine plot in file sine.png.pdf in page-size A4 into the
       
    96       current working directory.
       
    97    #. Save the sine plot in a file sine.png in png format with
       
    98       page-size A4 in the current working directory overriding the
       
    99       format argument
       
   100    #. Error in filename and format mismatch.
       
   101 
       
   102 Answer: Save the sine plot in file sine.png as a pdf file in page-size
       
   103 	A4 and saves it into the current working directory
       
   104 
       
   105 Larger Questions
       
   106 ----------------
       
   107 
       
   108 .. A minimum of 2 questions here (along with answers)
       
   109 
       
   110 1. Plot a cosine plot from -2pi to 2pi in green color taking 300
       
   111    points. Title the plot as 'Cosine plot' and the legend plot with
       
   112    'cos(x)'. And save the plot as a pdf file with the filename
       
   113    cosine_plot.
       
   114 
       
   115 2. Plot tan(x) where x varies from -4pi to 4pi in red color taking 600
       
   116    points. Title the plot as 'Tan plot' and the legend plot with
       
   117    'tan(x)'. And save the plot as a svg file with the filename
       
   118    tangent_plot.