In [11]:

    

n = 5

def median(X):
    return sorted(X)[len(X) // 2]

def median_of_medians(X):
    if len(X) <= n:
        return median(X)
    
    number_of_groups = len(X) // n
    medians = []
    for i in range(number_of_groups):
        medians.append(median_of_medians(X[i * n:n * (i + 1)]))
        
    return median_of_medians(medians)


    

In [12]:

    

median_of_medians(list(range(1, 11)))


    

    
Out[12]:





8

In [14]:

    

median_of_medians(list(range(1, 101)))


    

    
Out[14]:





63

In [21]:

    

median([1,2,3,4,5])


    

    
Out[21]:





3

In [22]:

    

median([6,7,8,9])


    

    
Out[22]:





8

In [23]:

    

median([3, 8])


    

    
Out[23]:





8

In [24]:

    

import numpy as np


    

In [25]:

    

np.mode([1,1,-1])


    

    




---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-25-e7db52396475> in <module>()
----> 1 np.mode([1,1,-1])

AttributeError: module 'numpy' has no attribute 'mode'

In [27]:

    

from collections import Counter


    

In [32]:

    

Counter([1,1,-1]).most_common(1)[0][0]


    

    
Out[32]:





1

In [34]:

    

2345 % 10


    

    
Out[34]:





5

In [35]:

    

2345 // 10


    

    
Out[35]:





234

In [36]:

    

def key(x, i):
    return (x // 10 ** i) % 10


    

In [39]:

    

key(123, 2)


    

    
Out[39]:





1

In [40]:

    

c = 1000

n = 10
n - 1 + n * (n + 1) / 2


    

    
Out[40]:





64.0

In [41]:

    

n ** 2


    

    
Out[41]:





100

In [52]:

    

a = [.75 ** i for i in range(100000)]
sum(a)


    

    
Out[52]:





3.9999999999999987

In [47]:

    




    

    
Out[47]:





3.7747459411621094

In [ ]: