--- a/accessing-pieces-arrays/questions.rst Wed Nov 17 23:24:57 2010 +0530
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,159 +0,0 @@
-Objective Questions
--------------------
-
-.. A mininum of 8 questions here (along with answers)
-
-1. Given the array, ``A = array([12, 15, 18, 21])``, how do we access
- the element ``18``?
-
- Answer: ``A[2]``
-
-#. Given the array, ``A = array([12, 15, 18, 21])``, what element is
- accessed by ``A[1]``
-
- Answer: ``15``
-
-#. Given the array, ``A = array([12, 15, 18, 21])``, what element is
- accessed by ``A[-3]``?
-
- Answer: ``15``
-
-#. Given the array, ``A = array([12, 15, 18, 21])``, how do you change
- the element ``15`` to ``51``?
-
- Answer: ``A[1] = 51``
-
-#. Given the array, ``A = array([12, 15, 18, 21])``, what is ``A``
- after the execution of the statement ``A[3] = 24``?
-
- Answer: ``array([12, 15, 18, 24])``
-
-#. Given the array, ``A = array([12, 15, 18, 21])``, what is the
- result of the statement, ``A[4] = 24``?
-
- Answer: IndexError: index out of bounds
-
-#. Given the array, ``B = array([[12, 15], [18, 21]])``, how do we
- access the element ``18``?
-
- Answer: ``A[0, 0]``
-
-#. Given the array, ``B = array([[12, 15], [18, 21]])``, what is the
- result of ``B[1]``?
-
- Answer: ``array([18, 21])``
-
-#. Given the array, ``B = array([[12, 15], [18, 21]])``, what is the
- result of ``B[1, 1]``?
-
- Answer: ``21``
-
-#. Given the array, ``B = array([[12, 15], [18, 21]])``, what element
- is accessed by ``B[-1, -2]``?
-
- Answer: ``18``
-
-#. Given the array, ``B = array([[12, 15], [18, 21]])``, how do you
- change the element ``15`` to ``51``?
-
- Answer: ``B[0, 1] = 51``
-
-#. Given the array, ``B = array([[12, 15], [18, 21]])``, what is the
- value of B, after executing, ``B[0] = 0``?
-
- Answer: ``array([[0, 0], [18, 21]])``
-
-#. Given the array,
-
- ::
-
- B = array([[10, 11, 12, 13],
- [20, 21, 22, 23],
- [30, 31, 32, 33],
- [40, 41, 42, 43]])
-
- Obtain the elements, ``[[21, 22], [32, 32]]``
-
- Answer: ``B[1:3, 1:3]``
-
-#. Given the array,
-
- ::
-
- B = array([[10, 11, 12, 13],
- [20, 21, 22, 23],
- [30, 31, 32, 33],
- [40, 41, 42, 43]])
-
- Obtain the elements, ``[[10, 13], [30, 33]]``
-
- Answer: ``B[::2, ::3]``
-
-#. What command is used to read an image file?
-
- a. imshow
- #. imread
- #. imopen
- #. open
-
- Answer: ``imread``
-
-#. If ``P`` is ``array([12, 13, 14, 15])`` then ``P.shape`` gives
- ``(4, 1)``. True or False?
-
- Answer: False
-
-Larger Questions
-----------------
-
-.. A minimum of 2 questions here (along with answers)
-
-1. Given the array,
- ::
-
- B = array([[10, 11, 12, 13],
- [20, 21, 22, 23],
- [30, 31, 32, 33],
- [40, 41, 42, 43]])
-
- Change the array to
- ::
-
- B = array([[10, 11, 10, 11],
- [20, 21, 20, 21],
- [10, 11, 10, 11],
- [20, 21, 20, 21]])
-
- using slicing and striding.
-
- Answer::
-
- B[:2, 2:] = B[:2, :2]
- B[2:, :2] = B[:2, :2]
- B[2:, 2:] = B[:2, :2]
-
-#. Find out how to display a grayscale image with proper colors. Hint,
- use ``?`` on ``imshow``.
-
- Answer: ``cmap=cm.gray``
-
-#. From the image, ``tagore-einstein.png``,
- a. show only the face of Einstein.
- b. show only the face of Tagore.
-
- Hint, use ``imread`` to read the image and ``imshow`` to show the
- image. Use ``cm.gray`` as ``cmap`` to display the image properly.
-
- Answer::
-
- F = imread('tagore-einstein.png')
- imshow(F[:210, 20:180], cmap=cm.gray)
-
- F = imread('tagore-einstein.png')
- imshow(F[30:300, 320:480], cmap=cm.gray)
-
-.. #[Puneeth: This question contains answer to previous
-.. question. Shouldn't be shown at the same time.]
-
-
-