diff -r 88a01948450d -r d33698326409 getting_started_with_arrays/questions.rst
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+++ b/getting_started_with_arrays/questions.rst	Wed Dec 01 16:51:35 2010 +0530
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+Objective Questions
+-------------------
+
+.. A mininum of 8 questions here (along with answers)
+
+1. An array in Python is the same as a Python list
+
+   a. True
+   #. False
+
+Answer: False
+
+2. ``x = array([1, 2, 3], [5, 6, 7])`` is a valid statement
+
+   a. True
+   #. False
+
+Answer: False
+
+3. What will be the output of the following code,
+   ::
+
+      x = array([[1, 2, 3], ['a', 2, 'c']])
+      print x[0][0] + x[0][1] + x[0][2] 
+
+   a. 6
+   #. 123
+   #. a2c
+   #. Error as array takes only homogeneous elements
+
+Answer: 123
+      
+4. What will be the output of the following code,
+   ::
+
+	x = [[1, 2, 3], [4.1, 4.2, 4.3], ['6','7',8]]
+	y = array(x)
+	print y[-1][-2] + y[-1][-1] + y[-2][0] + y[0][-2]
+
+   a. 21.1
+   #. 12.5
+   #. 784.12
+   #. Error as array takes only homogeneous elements
+
+   .. 4.2 4.3 2 2
+
+Answer: 784.12
+
+5. What is the output of the following code,
+   ::
+
+      x = array([[1, 2, 3], ['a', 2, 'c']])
+      identity(x.shape)
+
+   a. Will create an identity matrix of shape (2, 3).
+   #. ``identity()`` function takes an integer as argument and a tuple
+      is passed.
+   #. Will return, array([[1,0,1],[0,1,0]])
+   #. Will return, array([[0,1,0],[0,1,0]])
+
+Answer: ``identity()`` function takes an integer as argument and a
+      	tuple is passed.
+
+6. ``ones_like()`` function?
+   
+   (A) Returns an array of ones with the same shape and type as a
+       given array.
+   (B) Return a new array of given shape and type, filled with ones.
+
+   Read the statements and answer,
+
+   a. Only statement A is correct.
+   #. Only statement B is correct.
+   #. Both statement A and B are correct.
+   #. Both statement A and B are incorrect.
+
+Answer: Only statement A is correct.
+
+7. ``zeros_like()`` function?
+
+   (A) Return a new array of given shape and type, filled with zeros.
+   (B) Returns an array of zeros with the same shape and type as a
+       given array.
+
+
+   Read the statements and answer,
+
+   a. Only statement A is correct.
+   #. Only statement B is correct.
+   #. Both statement A and B are correct.
+   #. Both statement A and B are incorrect.
+
+Answer: Only statement B is correct.
+
+8. What will be output of the following code snippet.
+   ::
+
+      x = linspace(1,10,10).reshape(5,2)
+      print (x[-3]+x[-4]).sum()
+
+   a. 10.0 
+   #. 18.0
+   #. 14.0
+   #. 16.44
+   #. Error
+
+Answer: 18
+
+Larger Questions
+----------------
+
+.. A minimum of 2 questions here (along with answers)
+
+1. Write a python script to create a 15x15 array of equally spaced 225
+   elements from 1 to 1000, add 5 to each of the diagonal elements and
+   find the sum of all odd rows of the array. Say for example the
+   array,
+   ::
+
+       x = array([[1, 2, 3],
+		  [4, 5, 6],
+		  [7, 8, 9]])
+
+   will give answer 40 ((1+5) + 2 + 3 + 7 + 8 + (9+5)).
+
+2. For any given array([a1, a2, a3, .. , an]) the Vandermonde matrix
+    will be [[1, a1, a1**2, .. , a1**(n-1)], [1, a2, a2**2, .. ,
+    a2**(n-1)], .. , [1, an, an**2, .. ,an**(n-1)]]. Write a python
+    script to generate the Vandermonde matrix and find the determinant
+    of the matrix for [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+    16, 17, 18, 19, 20].  [Hint: to find the determinant use the
+    function ``det()`` from ``linalg`` module.]