使用如下方法对DataFrame进行数据过虑：

import pandas as pd
data = pd.read_csv('Haiti.csv')
print data[data['LATITUDE']>18 and data['LATITUDE']<20]

或

import pandas as pd
data = pd.read_csv('Haiti.csv')
print data[data.LATITUDE>18 and data.LATITUDE<20]

均会出现错误“ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().”
正确的做法是：

import pandas as pd
data = pd.read_csv('Haiti.csv')
print data[(data.LATITUDE>18) & (data.LATITUDE<20)]