In [25]:

    

# read population in
import json
import requests
from pandas import DataFrame

# pop_json_url holds a 
pop_json_url = "https://gist.github.com/rdhyee/8511607/raw/f16257434352916574473e63612fcea55a0c1b1c/population_of_countries.json"
pop_list= requests.get(pop_json_url, verify=False).json()

df = DataFrame(pop_list)
df[:5]


    

    
Out[25]:






  

    

      

      
0
      
1
      
2
    
  
  

    

      
0
      
 1
      
         China
      
 1385566537
    
    

      
1
      
 2
      
         India
      
 1252139596
    
    

      
2
      
 3
      
 United States
      
  320050716
    
    

      
3
      
 4
      
     Indonesia
      
  249865631
    
    

      
4
      
 5
      
        Brazil
      
  200361925
    
  

5 rows × 3 columns

In [26]:

    

pop_list[0]


    

    
Out[26]:





[1, u'China', 1385566537]

In [12]:

    

from pandas import DataFrame, Series, Index
import numpy as np

s1 = Series(np.arange(1,4))
s1


    

    
Out[12]:





0    1
1    2
2    3
dtype: int32

In [22]:

    

sum(df[df[1].str.startswith('C')][2])


    

    
Out[22]:





1667559248

In [24]:

    

1667559248>1385566537


    

    
Out[24]:





True

In [17]:

    

s1.apply(lambda k: 2*k)


    

    
Out[17]:





0    2
1    4
2    6
dtype: int64

In [18]:

    

s1.apply(lambda k: 2*k).sum()


    

    
Out[18]:





12

In [20]:

    

s1.cumsum()


    

    
Out[20]:





0    1
1    3
2    6
dtype: int32

In [21]:

    

s1.cumsum()[1]


    

    
Out[21]:





3