Array attributes

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import numpy as np
 
def test_run():
    a = np.random.random((5, 4))
    print a
    print a.shape
 
if __name__ == "__main__":
    test_run()
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import numpy as np
 
def test_run():
    a = np.random.random((5, 4))
    print a.size
 
if __name__ == "__main__":
    test_run()
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import numpy as np
 
def test_run():
    np.random.seed(693)
    a = np.random.randint(0, 10, size=(5, 4))
    print "Array:\n", a
 
if __name__ == "__main__":
    test_run()

Locate maximum value

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import numpy as np
 
def get_max_index(a):
    return a.argmax()
 
def test_run():
    a = np.array([9, 6, 2, 3, 12, 14, 7, 10], dtype=np.int32)
    print "Array:", a
 
    print "Maximum value", a.max()
    print "Index of max.:", get_max_index(a)
 
 
if __name__ == "__main__":
    test_run()

Timing python operations

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import time
 
def time_run():
    t1 = time.time()
    print "ML4T"
    t2 = time.time()
    print "The time taken by print statement is ",t2 - t1," seconds"
 
if __name__ == "__main__":
    test_run()

Accessing array element

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import numpy as np
 
def test_run():
    a = np.random.rand(5, 4)
    print "Array:\n", a
 
    element = a[3, 2]
    print element
 
if __name__ == "__main__":
    test_run()

Indexing an array with another array

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import numpy as np
 
def test_run():
    a = np.random.rand(5)
    indices = np.array([1,1,2,3])
    print a[indices]
 
if __name__ == "__main__":
    test_run()