DataFrames中的reindex用法

from pandas import DataFrame

frame = DataFrame(np.arange(9).reshape((3,3)),index=['a','c','d'],columns=['Ohio','Texas','California']

states = ['Texas','Utah','California']

 

frame.reindex(columns=states)

# a index赋值给b

frame.reindex(index=['a','b','c','d',method='ffill',columns=states)

# c index赋值给b

frame.reindex(index=['a','b','c','d',method='ffill',columns=states)