To filter a dataframe (df) by a single column, if we consider data with male and females we might:
males = df[df[Gender]=='Male']
Question 1 - But what if the data spanned multiple years and i wanted to only see males for 2014?
In other languages I might do something like:
if A = "Male" and if B = "2014" then
(except I want to do this and get a subset of the original dataframe in a new dataframe object)
Question 2. How do I do this in a loop, and create a dataframe object for each unique sets of year and gender (i.e. a df for: 2013-Male, 2013-Female, 2014-Male, and 2014-Female
for y in year:
for g in gender:
df = .....
Using &
operator, don't forget to wrap the sub-statements with ()
:
males = df[(df[Gender]=='Male') & (df[Year]==2014)]
To store your dataframes in a dict
using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'female']:
dic[g]=defaultdict(dict)
for y in [2013, 2014]:
dic[g][y]=df[(df[Gender]==g) & (df[Year]==y)] #store the DataFrames to a dict of dict
A demo for your getDF
:
def getDF(dic, gender, year):
return dic[gender][year]
print genDF(dic, 'male', 2014)