我遇到了这样的麻烦:我需要找到用户第一次点击一个电子邮件(变量发送),并在发生时在相应的行中放置一个。找到最早的发生
该数据集有几千个用户(散列)在通讯中点击电子邮件的一部分。我试图通过发送,哈希将它们分组,然后找到最早的日期,但无法使其工作。
所以我去了一小讨厌的解决方案,然而返回奇怪的事情:
我的数据集(相关变量):
>>> clicks[['datetime','hash','sending']].head()
datetime hash sending
0 2016-11-01 19:13:34 0b1f4745df5925dfb1c8f53a56c43995 5
1 2016-11-01 10:47:14 0a73d5953ebf5826fbb7f3935bad026d 5
2 2016-10-31 19:09:21 605cebbabe0ba1b4248b3c54c280b477 5
3 2016-10-31 13:42:36 d26d61fb10c834292803b247a05b6cb7 5
4 2016-10-31 10:46:30 48f8ab83e8790d80af628e391f3325ad 5
有6个发送回合,datetime
是datetime64[ns]
。
我这样做是如下的方式:
所有的clicks['first'] = 0
for hash in clicks['hash'].unique():
t = clicks.ix[clicks.hash==hash, ['hash','datetime','sending']]
part = t['sending'].unique()
for i in part:
temp = t.ix[t.sending == i,'datetime']
clicks.ix[t[t.datetime == np.min(temp)].index.values,'first']=1
首先,我不认为这是非常Python的,而且是相当缓慢的。但主要是它返回一个奇怪的类型!有0.0
和1.0
值,但我不能与他们合作:
>>> type(clicks.first)
<type 'instancemethod'>
>>> clicks.loc[clicks.first==1]
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/air/anaconda/lib/python2.7/site-packages/pandas/core/indexing.py", line 1296, in __getitem__
return self._getitem_axis(key, axis=0)
File "/Users/air/anaconda/lib/python2.7/site-packages/pandas/core/indexing.py", line 1467, in _getitem_axis
return self._get_label(key, axis=axis)
File "/Users/air/anaconda/lib/python2.7/site-packages/pandas/core/indexing.py", line 93, in _get_label
return self.obj._xs(label, axis=axis)
File "/Users/air/anaconda/lib/python2.7/site-packages/pandas/core/generic.py", line 1749, in xs
loc = self.index.get_loc(key)
File "/Users/air/anaconda/lib/python2.7/site-packages/pandas/indexes/base.py", line 1947, in get_loc
return self._engine.get_loc(self._maybe_cast_indexer(key))
File "pandas/index.pyx", line 137, in pandas.index.IndexEngine.get_loc (pandas/index.c:4154)
File "pandas/index.pyx", line 156, in pandas.index.IndexEngine.get_loc (pandas/index.c:3977)
File "pandas/index.pyx", line 373, in pandas.index.Int64Engine._check_type (pandas/index.c:7634)
KeyError: False
所以任何想法,请?非常感谢!
----- UPDATE:------
INSTALLED VERSIONS
------------------
commit: None
python: 2.7.12.final.0
python-bits: 64
OS: Darwin
OS-release: 15.6.0
machine: x86_64
processor: i386
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
pandas: 0.18.1
Wowza,谢谢!我尝试了lambda,但没有让它工作,不知道如何从中选择最小值。所以这看起来不错,但仍然不能对它进行分类,得到相同的错误。虽然'clicks.first'最终是整数。你知道为什么吗? –
也许你有重复最小值的问题。它对样本很好,并且真实的数据不是? – jezrael
每个'hash'和'sending'都不能有重复。该子集的错误说:'TypeError:不能在上使用这些索引器[False] '进行位置索引'所以它看起来不再是'DataFrame' –