我在我的数据框架上使用group Description，Week和Count来获取每周计数，如下所示：
Description Week count
527 N25846 External EMERGENCY STOP 2015-05-03 77
528 N25846 External EMERGENCY STOP 2015-05-10 983
529 N25846 External EMERGENCY STOP 2015-05-17 245
530 N25846 External EMERGENCY STOP 2015-05-24 897
531 N25846 External EMERGENCY STOP 2015-05-31 2144
532 N25846 External EMERGENCY STOP 2015-06-07 926
533 N25846 External EMERGENCY STOP 2015-06-14 1082
534 N25846 External EMERGENCY STOP 2015-06-21 1935
535 N25846 External EMERGENCY STOP 2015-06-28 1511
536 N25846 External EMERGENCY STOP 2015-07-05 3206
537 N25846 External EMERGENCY STOP 2015-07-12 2031
538 N25846 External EMERGENCY STOP 2015-07-19 590
539 N25846 External EMERGENCY STOP 2015-07-26 1085
540 N25846 External EMERGENCY STOP 2015-08-02 162
541 N25846 External EMERGENCY STOP 2015-08-09 922
542 N25846 External EMERGENCY STOP 2015-08-16 655
543 N25846 External EMERGENCY STOP 2015-08-23 114
544 N25846 External EMERGENCY STOP 2015-08-30 42
616 N38 Excessive servo lag in Z 2015-08-23 1
676 N418 Program start undefined 11 2015-08-23 1
679 N4226 8BD0 Excessive servo lag in V 2015-08-23 1
680 N4226 8BD0 Excessive servo lag in Y 2015-08-23 1
681 N4226 8BD0 Excessive servo lag in Z 2015-08-23 1
762 N51 Positioning error 2015-08-23 1
1471 P69 Tool magazine error# 3 2015-08-23 1
1567 P795 0-SIGNAL LUBRICATION FEEDBACK 2015-08-23 1
1908 Powerfail AC, HDD lock:15.08.2015 01:32:40.533... 2015-08-23 1
1976 number of missing logbook entries: 18 2015-08-23 1
175 N156 MP: not defined 2015-08-30 1
到达最后，我们看到空的周没有显示出来。有没有办法显示每个Description的空周数，其中没有数周显示？
所需输出：
Description Week count
N156 MP: not defined 2015-05-03 0
N156 MP: not defined 2015-05-10 0
N156 MP: not defined 2015-05-17 0
N156 MP: not defined 2015-05-24 0
N156 MP: not defined 2015-05-31 0
N156 MP: not defined 2015-06-07 0
N156 MP: not defined 2015-06-14 0
N156 MP: not defined 2015-06-21 0
N156 MP: not defined 2015-06-28 0
N156 MP: not defined 2015-07-05 0
N156 MP: not defined 2015-07-12 0
N156 MP: not defined 2015-07-19 0
N156 MP: not defined 2015-07-26 0
N156 MP: not defined 2015-08-02 0
N156 MP: not defined 2015-08-09 0
N156 MP: not defined 2015-08-16 0
N156 MP: not defined 2015-08-23 0
N156 MP: not defined 2015-08-30 1
答案 0 :(得分：1)
假设“空白周”＆＃39;缺少值（？）。 docs说
GroupBy中的NA组被自动排除。
如果是这个原因，您需要在.fillna(value)之前使用您选择的值来应用.groupby() - 例如0。