I have tried and searched for two days on this (I'm still quite the noob). Can anyone help me with this probably simple task?
I am practicing with data in this format:
df = DataFrame({'year':[2010]*5 + [2011]*5, 'names':['a','b','c','d','e']*2, 'births':[1,2,3,4,5,6,7,8,9,10]})
births names year
0 1 a 2010
1 2 b 2010
2 3 c 2010
3 4 d 2010
4 5 e 2010
5 6 a 2011
6 7 b 2011
7 8 c 2011
8 9 d 2011
9 10 e 2011
And I want to get it in this format:
Year Name births
2010 a 1
b 2
c 3
d 4
e 5
2011 a 6
b 7
c 8
d 9
e 10
I want it like this so I can easily access it with a combined primary key like df.ix('2010','a') --- I don't know if this is even possible or if it is how to reference it
Can anyone explain how I do this? Thank you!
df = df.set_index(['year', 'names']) will give you what you want. You can access elements as
In[781]: df.set_index(['year', 'names']).xs(2010)
Out[777]:
births
names
a 1
b 2
c 3
d 4
e 5
In[782]: df.set_index(['year', 'names']).xs([2010, 'a'])
Out[778]:
births 1
Name: (2010, a), dtype: int64