如何分组和基于总和过滤数据帧？

时间：2020-09-01 20:05:00

标签： python pandas dataframe pandas-groupby

所以我有一个数据框milk_countries_exports，由以下各列组成：

  • “ Period”，特定行的年和月（数据集是一年中逐月）
  • 正在执行出口的“报告人”国家/地区
  • 从“报告者”导入的“合作伙伴”国家/地区
  • “商品”由两个项目组成，“既未浓缩也未加糖的牛奶和奶油”和“浓缩或未加糖的牛奶和奶油”
  • “商品代码”是分配给商品类型的编号，因此分别为“ 0401”和“ 0402”
  • “贸易价值（美元）”，即该行在给定月份，国家和商品类型下发生的贸易额

The first few rows of the dataframe milk_countries_exports

我被要求做

过滤数据集，使其仅包含总计的行 特定国家/地区所有奶制品的出口量为 在任何给定的每月期间内至少获得200万美元。 （提示：分组 合作伙伴和期间，并针对测试 最低交易价值超过了要求的价值。）

对我来说，这似乎意味着每个给定的月份和每个合作伙伴，如果该月（例如201401）和合作伙伴（例如德国）的0401和0402之和大于200万美元，则保留这两行，否则过滤他们出来。因此，如果对于一个月度伙伴对，您分别为0401和0402分别具有900,000和2,000,000的值，总和为2,900,000，那么即使其中一行小于200万阈值，两行都将保留，因为它已经超出了0401和0402的总和，而不是它们各自的值。

作为数据中的参考点，我使用了“德国”的前几行，因为作为伙伴，它同时包含0401和0402的示例（许多伙伴只有一个或另一个），而至关重要的是第一个月包含0401低于982240的200万阈值，而0402低于3187636的阈值。因此，如果过滤后这些行中的一者或两者均丢失，我知道我做错了。

The first few rows of partner Germany within the dataframe milk_countries_exports

我尝试以这种方式应用它：

我定义了一个函数，用于测试数据集是否满足大于或等于200万的条件：

def groupsWithExportsOver2million (g): 

    return g['Trade Value (US$)'].min() >= 2000000

然后：

milk_countries_exports[milk_countries_exports['Partner'] == 'Germany'].groupby(['Period', 'Partner']).filter(groupsWithExportsOver2million)

哪个会产生一个完全空白的数据帧，并且：

milk_countries_exports[milk_countries_exports['Period'] == '201401'].groupby(['Period', 'Partner']).filter(groupsWithExportsOver2million)

相同。但是：

milk_countries_exports.groupby(['Period', 'Partner']).filter(groupsWithExportsOver2million).sort_values('Trade Value (US$)')

（即显示整个数据集，而不只是显示一个国家或期间组）会产生一个56行的数据框，其中仅包含超过200万行的“贸易价值（美元）”行，我想不确定，它的过滤方式是说，如果任何伙伴国家或任何期间值在数据框中的贸易值小于200万，那么整个国家或期间值就会从结果数据框中消除。或者，换句话说，只留下一个表，该表仅包含每个实例中“贸易价值”的每个值都在200万以上的国家和月份。

我可以组合每个国家/时段对的0401和0402的值，并根据过滤器测试该总和，但是当然返回一个数据帧，其中0401和0402被组合为一个值，而实际上要做的是能够对它们求和，测试滤波器，然后取消组合它们，以便仍然分别存在0401和0402。

我该怎么做？

数据：

# copy data and create dataframe with 
df = pd.read_clipboard(sep=',')

Period,Reporter,Partner,Commodity,Commodity Code,Trade Value (US$)
2014-09-01,United Kingdom,World,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,33279381
2014-09-01,United Kingdom,Australia,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,4558
2014-09-01,United Kingdom,Austria,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,290
2014-09-01,United Kingdom,Barbados,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3016
2014-09-01,United Kingdom,Belgium,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,578297
2014-09-01,United Kingdom,Br. Virgin Isds,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,33746
2014-09-01,United Kingdom,Canada,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,34657
2014-09-01,United Kingdom,China,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1547888
2014-09-01,United Kingdom,Cyprus,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,20199
2014-09-01,United Kingdom,Denmark,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,89685
2014-09-01,United Kingdom,Falkland Isds (Malvinas),Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,35560
2014-09-01,United Kingdom,Finland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,141693
2014-09-01,United Kingdom,France,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,599127
2014-09-01,United Kingdom,Germany,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,587925
2014-09-01,United Kingdom,Gibraltar,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,29503
2014-09-01,United Kingdom,Greece,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,55
2014-09-01,United Kingdom,Guyana,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,74259
2014-09-01,United Kingdom,"China, Hong Kong SAR",Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,73082
2014-09-01,United Kingdom,Hungary,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,4141
2014-09-01,United Kingdom,Ireland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,28619275
2014-09-01,United Kingdom,Italy,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,11989
2014-09-01,United Kingdom,Japan,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3337
2014-09-01,United Kingdom,Lithuania,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,275
2014-09-01,United Kingdom,Malta,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3756
2014-09-01,United Kingdom,"Other Asia, nes",Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,5040
2014-09-01,United Kingdom,Netherlands,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,406087
2014-09-01,United Kingdom,Portugal,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3939
2014-09-01,United Kingdom,Qatar,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,10796
2014-09-01,United Kingdom,Saint Helena,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3323
2014-09-01,United Kingdom,Singapore,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,10254
2014-09-01,United Kingdom,Viet Nam,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,10529
2014-09-01,United Kingdom,Slovenia,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,11
2014-09-01,United Kingdom,South Africa,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,8067
2014-09-01,United Kingdom,Spain,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,210956
2014-09-01,United Kingdom,Trinidad and Tobago,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,9680
2014-09-01,United Kingdom,United Arab Emirates,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,37348
2014-09-01,United Kingdom,United States of America,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,67035
2014-05-01,United Kingdom,World,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,21665661
2014-05-01,United Kingdom,Denmark,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2311364
2014-05-01,United Kingdom,France,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1638838
2014-05-01,United Kingdom,Germany,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2199671
2014-05-01,United Kingdom,Italy,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,9950
2014-09-01,United Kingdom,World,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,27320918
2014-09-01,United Kingdom,Algeria,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,1659167
2014-09-01,United Kingdom,Angola,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,923506
2014-09-01,United Kingdom,Austria,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,443
2014-09-01,United Kingdom,Bangladesh,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,895167
2014-09-01,United Kingdom,Barbados,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,2027
2014-09-01,United Kingdom,Belgium,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,83721
2014-09-01,United Kingdom,Cameroon,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,83356
2014-09-01,United Kingdom,Sri Lanka,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,15332
2014-09-01,United Kingdom,China,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,1460603
2014-09-01,United Kingdom,Congo,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,673852
2014-09-01,United Kingdom,Cuba,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,849676
2014-09-01,United Kingdom,Cyprus,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,13521
2014-09-01,United Kingdom,Benin,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,112444
2014-09-01,United Kingdom,Denmark,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,63293
2014-09-01,United Kingdom,Dominican Rep.,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,535019
2014-09-01,United Kingdom,Finland,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,209
2014-09-01,United Kingdom,France,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,262833
2014-09-01,United Kingdom,Germany,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,2921594
2014-09-01,United Kingdom,Greece,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,52
2014-09-01,United Kingdom,Guinea,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,441798
2014-09-01,United Kingdom,Guyana,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,65483
2014-09-01,United Kingdom,"China, Hong Kong SAR",Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,1210921
2014-09-01,United Kingdom,Hungary,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,28794
2014-09-01,United Kingdom,Iraq,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,111141
2014-09-01,United Kingdom,Ireland,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,5498955
2014-09-01,United Kingdom,Italy,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,4204
2014-09-01,United Kingdom,Côte d'Ivoire,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,2322223
2014-09-01,United Kingdom,Jamaica,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,131078
2014-09-01,United Kingdom,Kuwait,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,623076
2014-09-01,United Kingdom,Lebanon,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,388137
2014-09-01,United Kingdom,Latvia,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,37
2014-09-01,United Kingdom,Malaysia,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,284043
2014-09-01,United Kingdom,Mali,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,220000
2014-09-01,United Kingdom,Malta,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,12190
2014-09-01,United Kingdom,Mauritania,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,73724
2014-09-01,United Kingdom,Mauritius,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,108406
2014-09-01,United Kingdom,Netherlands,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,979298
2014-09-01,United Kingdom,Nigeria,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,308385
2014-09-01,United Kingdom,Norway,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,5736
2014-09-01,United Kingdom,Pakistan,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,8151
2014-09-01,United Kingdom,Panama,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,142387
2014-05-01,United Kingdom,Lithuania,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,9354
2014-05-01,United Kingdom,Netherlands,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,664032
2014-05-01,United Kingdom,Portugal,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,912
2014-05-01,United Kingdom,Romania,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,225281
2014-05-01,United Kingdom,Slovakia,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,45434
2014-05-01,United Kingdom,Sweden,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,64547
2014-05-01,United Kingdom,United Arab Emirates,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,6742
2014-05-01,United Kingdom,Belgium,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2707248
2014-05-01,United Kingdom,Ireland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,11065926
2014-05-01,United Kingdom,Poland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,716363
2014-10-01,United Kingdom,World,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,26615557
2014-10-01,United Kingdom,Austria,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,745
2014-10-01,United Kingdom,Belgium,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,609637
2014-10-01,United Kingdom,Bermuda,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1439
2014-10-01,United Kingdom,Canada,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,27639
2014-10-01,United Kingdom,Sri Lanka,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2230
2014-10-01,United Kingdom,China,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1493672
2014-10-01,United Kingdom,Cyprus,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,5509
2014-10-01,United Kingdom,Denmark,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,72569
2014-10-01,United Kingdom,Falkland Isds (Malvinas),Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,15189
2014-10-01,United Kingdom,Finland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,184498
2014-10-01,United Kingdom,France,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,658064
2014-10-01,United Kingdom,Germany,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,936431
2014-10-01,United Kingdom,Gibraltar,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,13367
2014-10-01,United Kingdom,Guatemala,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,200251
2014-10-01,United Kingdom,"China, Hong Kong SAR",Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,265362
2014-10-01,United Kingdom,Hungary,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,11
2014-10-01,United Kingdom,Ireland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,21360068
2014-10-01,United Kingdom,Italy,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,12806
2014-10-01,United Kingdom,Japan,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2127
2014-10-01,United Kingdom,Rep. of Korea,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,18549
2014-10-01,United Kingdom,Luxembourg,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,58
2014-10-01,United Kingdom,Malta,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,14189
2014-10-01,United Kingdom,Netherlands,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,337973
2014-10-01,United Kingdom,Portugal,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3142
2014-10-01,United Kingdom,Singapore,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,8653
2014-10-01,United Kingdom,Viet Nam,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,10406
2014-10-01,United Kingdom,South Africa,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,7512
2014-10-01,United Kingdom,Spain,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,195426
2014-10-01,United Kingdom,United Arab Emirates,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,37325
2014-10-01,United Kingdom,Ukraine,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2587
2014-10-01,United Kingdom,United States of America,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,118121
2014-07-01,United Kingdom,World,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,39508127
2014-07-01,United Kingdom,Afghanistan,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,4017
2014-07-01,United Kingdom,Austria,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,365
2014-07-01,United Kingdom,Bahrain,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3348
2014-07-01,United Kingdom,Belgium,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,842327
2014-07-01,United Kingdom,Bermuda,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2062
2014-07-01,United Kingdom,Br. Virgin Isds,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,39168
2014-07-01,United Kingdom,Canada,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,33987
2014-07-01,United Kingdom,Sri Lanka,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3170
2014-07-01,United Kingdom,China,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1178497
2014-07-01,United Kingdom,Cyprus,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,21465
2014-07-01,United Kingdom,Denmark,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,111562
2014-07-01,United Kingdom,Falkland Isds (Malvinas),Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,23319
2014-07-01,United Kingdom,Finland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,135463
2014-07-01,United Kingdom,France,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,3606510
2014-07-01,United Kingdom,Germany,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,898346
2014-07-01,United Kingdom,Gibraltar,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,8565
2014-07-01,United Kingdom,Greece,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1743
2014-07-01,United Kingdom,"China, Hong Kong SAR",Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,665185
2014-07-01,United Kingdom,Hungary,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,8635
2014-07-01,United Kingdom,Ireland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,29943028
2014-07-01,United Kingdom,Italy,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,14349
2014-07-01,United Kingdom,Japan,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,7631
2014-07-01,United Kingdom,Rep. of Korea,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,2489
2014-07-01,United Kingdom,Malta,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,23238
2014-07-01,United Kingdom,Netherlands,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1424401
2014-07-01,United Kingdom,Portugal,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,9260
2014-07-01,United Kingdom,Singapore,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,7865
2014-07-01,United Kingdom,Viet Nam,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,11085
2014-07-01,United Kingdom,South Africa,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,9104
2014-07-01,United Kingdom,Spain,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,311615
2014-07-01,United Kingdom,Sweden,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,792
2014-07-01,United Kingdom,Switzerland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1444
2014-07-01,United Kingdom,United Arab Emirates,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,25733
2014-07-01,United Kingdom,United States of America,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,128358
2014-06-01,United Kingdom,World,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,16022428
2014-06-01,United Kingdom,Belgium,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1346169
2014-06-01,United Kingdom,Denmark,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1972893
2014-06-01,United Kingdom,France,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1449614
2014-06-01,United Kingdom,Germany,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,1856919
2014-06-01,United Kingdom,Ireland,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,7597407
2014-06-01,United Kingdom,Italy,Milk and cream; not concentrated nor containing added sugar or other sweetening matter,0401,8011
2014-09-01,United Kingdom,Poland,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,528311
2014-09-01,United Kingdom,Portugal,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,4418
2014-09-01,United Kingdom,Saint Lucia,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,11489
2014-09-01,United Kingdom,Saudi Arabia,Milk and cream; concentrated or containing added sugar or other sweetening matter,0402,715791

尝试解决方案时出现错误消息：

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-131-1bce8906203d> in <module>
----> 1 df_filtered = milk_countries_exports.groupby(['Partner', pd.Grouper(key='Period', freq='1M')]).filter(lambda x: x['Trade Value (US$)'].sum() > 2000000)

~\anaconda3\lib\site-packages\pandas\core\frame.py in groupby(self, by, axis, level, as_index, sort, group_keys, squeeze, observed)
   5808             group_keys=group_keys,
   5809             squeeze=squeeze,
-> 5810             observed=observed,
   5811         )
   5812 

~\anaconda3\lib\site-packages\pandas\core\groupby\groupby.py in __init__(self, obj, keys, axis, level, grouper, exclusions, selection, as_index, sort, group_keys, squeeze, observed, mutated)
    407                 sort=sort,
    408                 observed=observed,
--> 409                 mutated=self.mutated,
    410             )
    411 

~\anaconda3\lib\site-packages\pandas\core\groupby\grouper.py in get_grouper(obj, key, axis, level, sort, observed, mutated, validate)
    623                 in_axis=in_axis,
    624             )
--> 625             if not isinstance(gpr, Grouping)
    626             else gpr
    627         )

~\anaconda3\lib\site-packages\pandas\core\groupby\grouper.py in __init__(self, index, grouper, obj, name, level, sort, observed, in_axis)
    294             # check again as we have by this point converted these
    295             # to an actual value (rather than a pd.Grouper)
--> 296             _, grouper, _ = self.grouper._get_grouper(self.obj, validate=False)
    297             if self.name is None:
    298                 self.name = grouper.result_index.name

~\anaconda3\lib\site-packages\pandas\core\resample.py in _get_grouper(self, obj, validate)
   1409     def _get_grouper(self, obj, validate: bool = True):
   1410         # create the resampler and return our binner
-> 1411         r = self._get_resampler(obj)
   1412         r._set_binner()
   1413         return r.binner, r.grouper, r.obj

~\anaconda3\lib\site-packages\pandas\core\resample.py in _get_resampler(self, obj, kind)
   1402 
   1403         raise TypeError(
-> 1404             "Only valid with DatetimeIndex, "
   1405             "TimedeltaIndex or PeriodIndex, "
   1406             f"but got an instance of '{type(ax).__name__}'"

TypeError: Only valid with DatetimeIndex, TimedeltaIndex or PeriodIndex, but got an instance of 'Int64Index'

1 个答案:

答案 0 :(得分：3)

  • g['Trade Value (US$)'].min() >= 2000000过滤掉所有内容，因为这意味着最小值必须大于2000000。
  • 使用pandas.Grouper以指定的频率对Period进行分组。
  • pandas.core.groupby.DataFrameGroupBy.filter以根据'Trade Value (US$)'的总和进行过滤。
    • x['Trade Value (US$)'].sum() > 2000000是过滤器功能。可以将其放入外部def函数中，但这不是必需的。
  • Commodity Code也可以添加到分组依据：
    • groupby(['Partner', 'Commodity Code', pd.Grouper(key='Period', freq='1M')]) 
import pandas as pd

# load the data
df = pd.read_csv('https://raw.githubusercontent.com/trenton3983/stack_overflow/master/data/so_data/2020-09-01%2063694704/comtrade.csv', dtype={'Commodity Code': str})

# select desired columns
df = df.loc[:, ['Period', 'Reporter', 'Partner', 'Commodity', 'Commodity Code', 'Trade Value (US$)']]

# convert Period to datetime format
df.Period = pd.to_datetime(df.Period, format='%Y%m')

# display(df.head(3))
      Period        Reporter    Partner                                                                               Commodity Commodity Code  Trade Value (US$)
0 2014-09-01  United Kingdom      World  Milk and cream; not concentrated nor containing added sugar or other sweetening matter           0401           33279381
1 2014-09-01  United Kingdom  Australia  Milk and cream; not concentrated nor containing added sugar or other sweetening matter           0401               4558
2 2014-09-01  United Kingdom    Austria  Milk and cream; not concentrated nor containing added sugar or other sweetening matter           0401                290

# groupby Partner and month, and filter by sum of Trade value > 2000000
df_filtered = df.groupby(['Partner', pd.Grouper(key='Period', freq='1M')]).filter(lambda x: x['Trade Value (US$)'].sum() > 2000000)

# verify the period Trade Value sums per partner per month are > 2000000
df_filtered.groupby(['Partner', pd.Grouper(key='Period', freq='1M')]).agg({'Trade Value (US$)': sum})

[out]:
                                 Trade Value (US$)
Partner              Period                       
Algeria              2014-01-31            4792662
                     2014-02-28            7220679
                     2014-03-31            9835523
                     2014-04-30           14875816
                     2014-05-31           19656679
                     2014-06-30           22411564
                     2014-07-31            3214364
                     2014-10-31            4074424
                     2014-11-30            2107597
                     2014-12-31            3464600
Angola               2014-03-31            2324977
                     2014-12-31            2030001
Belgium              2014-01-31           14531571
                     2014-02-28            6955784
                     2014-03-31            9576248
                     2014-04-30            8569745
                     2014-05-31            7635442
                     2014-06-30            5435766
                     2014-07-31            5128432
                     2014-08-31            5169545
                     2014-09-30            5707207
                     2014-10-31            4982965
                     2014-11-30            8547975
                     2014-12-31            5441072
China                2014-03-31            2460056
                     2014-07-31            2778780
                     2014-09-30            3008491
                     2014-10-31            4777912
                     2014-11-30            3774279
                     2014-12-31            3045122
China, Hong Kong SAR 2014-01-31            2170443
                     2014-07-31            2048469
                     2014-11-30            2049788
Côte d'Ivoire        2014-03-31            2842636
                     2014-06-30            2499308
                     2014-08-31            2173727
                     2014-09-30            2322223
Denmark              2014-01-31            2399943
                     2014-02-28            2136906
                     2014-03-31            2523950
                     2014-04-30            2523958
                     2014-05-31            2490132
                     2014-06-30            2191829
                     2014-07-31            3180516
                     2014-08-31            2497068
                     2014-09-30            3052401
                     2014-10-31            3019545
                     2014-11-30            2929672
                     2014-12-31            4497179
France               2014-01-31           12651302
                     2014-02-28           10284508
                     2014-03-31           14342231
                     2014-04-30           12846655
                     2014-05-31           12826328
                     2014-06-30           11756821
                     2014-07-31           13075198
                     2014-08-31            9966348
                     2014-09-30           10636585
                     2014-10-31           11120326
                     2014-11-30           10612800
                     2014-12-31            9512056
Germany              2014-01-31            9744449
                     2014-02-28            7688820
                     2014-03-31            8956210
                     2014-04-30           10604432
                     2014-05-31           10207829
                     2014-06-30           10104134
                     2014-07-31            7074641
                     2014-08-31            7768101
                     2014-09-30           12061074
                     2014-10-31           13060791
                     2014-11-30            8306606
                     2014-12-31            7132246
Ghana                2014-01-31            2389385
Guinea               2014-04-30            2098146
                     2014-05-31            2179330
Ireland              2014-01-31           57621249
                     2014-02-28           53529377
                     2014-03-31           52525722
                     2014-04-30           55134986
                     2014-05-31           57244611
                     2014-06-30           56814970
                     2014-07-31           52322023
                     2014-08-31           45421969
                     2014-09-30           51185200
                     2014-10-31           38818201
                     2014-11-30           37431831
                     2014-12-31           37494188
Lebanon              2014-07-31            2359805
Netherlands          2014-01-31           15376408
                     2014-02-28            9160546
                     2014-03-31           11064742
                     2014-04-30           15584558
                     2014-05-31           13182208
                     2014-06-30           14262841
                     2014-07-31           10843821
                     2014-08-31            7521907
                     2014-09-30            8164473
                     2014-10-31           13886896
                     2014-11-30           14965454
                     2014-12-31            6844463
Nigeria              2014-08-31            4676807
Poland               2014-09-30            2680608
                     2014-11-30            2694120
Spain                2014-01-31            2075305
                     2014-09-30            3185937
                     2014-10-31            2421800
                     2014-11-30            2318918
World                2014-01-31          139512730
                     2014-02-28          111789785
                     2014-03-31          131100878
                     2014-04-30          139406387
                     2014-05-31          144276262
                     2014-06-30          144420208
                     2014-07-31          117675469
                     2014-08-31          102032532
                     2014-09-30          117302843
                     2014-10-31          113368963
                     2014-11-30          106377174
                     2014-12-31           95273667
Yemen                2014-08-31            3311725

资源

  • Comtrade Data Analysis-这是我发现如何获取数据的地方
  • UN Comtrade Database-此处提供数据
    • 产品类型：商品
    • 频率：每月
    • 时期：2014年全年
    • 记者：英国
    • 合作伙伴：全部
    • 流量：进出口
    • HS（据报道）商品代码：0401（牛奶和奶油，既不浓缩也不甜）和0402（牛奶和奶油，不浓缩或甜）
    • 单击“预览”将显示一条消息，提示数据超过500行。数据是使用“下载CSV”按钮下载的，下载文件已正确重命名。
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