DataFrame
import pandas as pd data = {'state': ['Ohio', 'Ohio', 'Ohio', 'Nevada', 'Nevada'],'year': [2000, 2001, 2002, 2001, 2002],'pop': [1.5, 1.7, 3.6, 2.4, 2.9]} # 建立DataFrame对象 frame1 = pd.DataFrame(data)
In [73]: frame1 Out[73]: pop state year 0 1.5 Ohio 2000 1 1.7 Ohio 2001 2 3.6 Ohio 2002 3 2.4 Nevada 2001 4 2.9 Nevada 2002
在建立过程中可以指点列的顺序:
frame1 = pd.DataFrame(data,columns=['year', 'state', 'pop']) frame1
In [75]: frame1 Out[75]: year state pop 0 2000 Ohio 1.5 1 2001 Ohio 1.7 2 2002 Ohio 3.6 3 2001 Nevada 2.4 4 2002 Nevada 2.9
和Series一样,DataFrame也是可以指定索引内容:
In [76]: ind = ['one', 'two', 'three', 'four', 'five'] In [77]: frame1 = DataFrame(data,index = ind) In [78]: frame1 Out[78]: pop state year one 1.5 Ohio 2000 two 1.7 Ohio 2001 three 3.6 Ohio 2002 four 2.4 Nevada 2001 five 2.9 Nevada 2002