在使用Python處理數(shù)據(jù)時(shí),經(jīng)常需要對數(shù)據(jù)篩選。
這是在對時(shí)間篩選時(shí),判斷兩列時(shí)間是否相差一年,如果是,則返回符合條件的所有列。
data原始數(shù)據(jù):
data[map(lambda x:datetime.date(x.year-1,x.month,x.day),data['report_date'])==data['date_1y_ago']] company_id signal_code_x signal_value_x report_date signal_code_y signal_value_y report_date_last date_1y_ago 0 2154888 r_1002030000 0.62660 2015-09-30 r_1002030000 0.64145 2015-12-31 2014-12-31 1 2154888 r_1002030000 0.64145 2015-12-31 r_1002030000 0.64145 2015-12-31 2014-12-31 2 2154888 r_1002030000 0.60544 2015-03-31 r_1002030000 0.64145 2015-12-31 2014-12-31 3 2154888 r_1002030000 0.54911 2014-12-31 r_1002030000 0.64145 2015-12-31 2014-12-31 4 2154888 r_1002030000 0.61379 2015-06-30 r_1002030000 0.64145 2015-12-31 2014-12-31 5 1702887 r_1002030000 0.62173 2014-03-31 r_1002030000 0.51103 2015-03-31 2014-03-31 6 1702887 r_1002030000 0.55175 2014-12-31 r_1002030000 0.51103 2015-03-31 2014-03-31 7 1702887 r_1002030000 0.51103 2015-03-31 r_1002030000 0.51103 2015-03-31 2014-03-31 8 1702887 r_1002030000 0.58696 2014-06-30 r_1002030000 0.51103 2015-03-31 2014-03-31 9 13484491 r_1002030000 0.17658 2014-12-31 r_1002030000 0.41082 2015-12-31 2014-12-31 10 13484491 r_1002030000 0.41082 2015-12-31 r_1002030000 0.41082 2015-12-31 2014-12-31 11 13484491 r_1002030000 0.39220 2015-09-30 r_1002030000 0.41082 2015-12-31 2014-12-31