Arrays for Numerical work?

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a = [1,2,3]
b = [4,5,6]
c = a+b
print(c)


    

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a.append(b)
print(a)


    

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def sum(data):
    """ sum the elements of an array
    """
    asum = 0.0
    for i in data:
        asum = asum + i
    return asum


    

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# the length of the array is defined here, and re-used below
# to test performance, we can make this number very large 
# 1000, 1000000 etc.

n = 10


    

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%%time
a = list(range(n))


    

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%%time
print(sum(a))


    

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import numpy as np


    

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%%time
a=np.arange(n)


    

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%%time
print(sum(a))


    

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#%%time
%time print(a.sum())
%time print(a.sum())


    

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a=np.arange(10)
b=np.arange(10)
c = a + b
d = 3*a*a + b + 2.0
print(c)
print(d)


    

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c.shape


    

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c2=c.reshape(5,2)
c3=c.reshape(2,5)


    

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print(c)
print(c2)
print(c3)
type(c)


    

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c[0]=999


    

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print(c2)


    

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d2=c.reshape(5,2)[1:3,:]


    

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print(d2)


    

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d2[1,1]=888


    

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print(c)


    

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print(c2)