saving_plots/questions.rst
author Anoop Jacob Thomas<anoop@fossee.in>
Sat, 18 Dec 2010 12:54:49 +0530
changeset 524 b602b4dcc87d
parent 522 d33698326409
permissions -rw-r--r--
Made some changes to the script embellishing a plot, but it still needs changes.
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
522
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     1
Objective Questions
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     2
-------------------
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     3
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     4
.. A mininum of 8 questions here (along with answers)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     5
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     6
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     7
1. What argument can be used with savefig to increase the resolution
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     8
   of the plot while saving a plot.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
     9
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    10
   a. fname
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    11
   #. transparency
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    12
   #. dpi
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    13
   #. format
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    14
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    15
Answer: dpi
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    16
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    17
2. The fname argument of savefig has to be always absolute path.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    18
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    19
   a. True
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    20
   #. False
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    21
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    22
Answer: False
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    23
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    24
3. You are right now in the directory `/home/fossee`, from the
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    25
   following which one is the correct one in-order to save the plot as
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    26
   svg with the filename `plot` to the directory `/home/fossee/sine/`
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    27
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    28
   a. savefig('/sine/plot.svg')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    29
   #. savefig('sine/plot.svg')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    30
   #. savefig('home/fossee/sine/plot.svg')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    31
   #. All of these
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    32
   #. None of the above
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    33
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    34
Answer: savefig('sine/plot.svg')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    35
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    36
4. Which is the best image format to be used with Latex documents
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    37
   which savefig supports?
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    38
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    39
   a. SVG - Scalable Vector Graphics
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    40
   #. EPS - Encapsulated Post Script
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    41
   #. PS - Post Script
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    42
   #. PNG - Portable Network Graphics
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    43
   #. None of the above
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    44
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    45
Answer: EPS - Encapsulated Post Script
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    46
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    47
5. ``savefig('sine.png')`` saves the plot in,
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    48
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    49
   a. The root directory ``/`` (on GNU/Linux, Unix based systems)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    50
      ``c:\`` (on windows).
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    51
   #. Will result in an error as full path is not supplied.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    52
   #. The current working directory.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    53
   #. Predefined directory like ``/documents``.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    54
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    55
Answer: The current working directory.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    56
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    57
6. Study the following code and tell what will happen,
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    58
   ::
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    59
      savefig('cosine.png',facecolor='blue')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    60
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    61
   a. Will generate an error as plot statements are missing
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    62
   #. Will generate an error as full path is not specified
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    63
   #. Create a file ``cosine.png`` with blue background at the current
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    64
      working directory.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    65
   #. Create a file ``cosine.png`` with blue background at a
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    66
      predefined directory like ``/documents``.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    67
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    68
Answer: Create a file ``cosine.png`` with blue background at the
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    69
	current working directory.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    70
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    71
7. How to save the below plot as ``sine_green_border.png`` with green
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    72
   color border/edge in the current working directory.  The plot is given
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    73
   as,
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    74
   ::
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    75
	x = linspace(-5*pi,5*pi,200)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    76
	plot(x,sin(x),linewidth=2)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    77
	legend(['sin(x)'])
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    78
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    79
   a. ``savefig('sine_green_border.png',bordercolor='green')``
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    80
   #. ``savefig('sine_green_border.png',facecolor='green')``
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    81
   #. ``savefig('sine_green_border.png',edgecolor='green')``
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    82
   #. ``savefig('/sine_green_border.png',bordercolor='green')``
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    83
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    84
Answer: savefig('sine_green_border.png',edgecolor='green')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    85
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    86
8. Given the below code snippet, what does it do?
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    87
   ::
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    88
	x = linspace(-5*pi,5*pi,200)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    89
	plot(x,sin(x),linewidth=2)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    90
	legend(['sin(x)'])
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    91
    	savefig('sine.png',format='pdf',papertype='a4')
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    92
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    93
   a. Save the sine plot in file sine.png as a pdf file in page-size
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    94
      A4 and saves it into the current working directory
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    95
   #. Save the sine plot in file sine.png.pdf in page-size A4 into the
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    96
      current working directory.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    97
   #. Save the sine plot in a file sine.png in png format with
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    98
      page-size A4 in the current working directory overriding the
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
    99
      format argument
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   100
   #. Error in filename and format mismatch.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   101
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   102
Answer: Save the sine plot in file sine.png as a pdf file in page-size
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   103
	A4 and saves it into the current working directory
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   104
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   105
.. #[Puneeth: Good questions, but can we use it in quiz? most of it
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   106
.. has not been taught in the tutorial.]
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   107
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   108
Larger Questions
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   109
----------------
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   110
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   111
.. A minimum of 2 questions here (along with answers)
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   112
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   113
1. Plot a cosine plot from -2pi to 2pi in green color taking 300
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   114
   points. Title the plot as 'Cosine plot' and the legend plot with
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   115
   'cos(x)'. And save the plot as a pdf file with the filename
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   116
   cosine_plot.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   117
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   118
2. Plot tan(x) where x varies from -4pi to 4pi in red color taking 600
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   119
   points. Title the plot as 'Tan plot' and the legend plot with
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   120
   'tan(x)'. And save the plot as a svg file with the filename
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   121
   tangent_plot.
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   122
d33698326409 Renamed all LOs to match with their names in progress.org.
Puneeth Chaganti <punchagan@fossee.in>
parents:
diff changeset
   123