Python 列出熊猫组中最常见的成员?
我有一个dataframe,其中的列如下:Python 列出熊猫组中最常见的成员?,python,sorting,pandas,dataframe,series,Python,Sorting,Pandas,Dataframe,Series,我有一个dataframe,其中的列如下: id lead_sponsor lead_sponsor_class 02837692 Janssen Research & Development, LLC Industry 02837679 Aarhus University Hospital Other 02837666 Unive
id lead_sponsor lead_sponsor_class
02837692 Janssen Research & Development, LLC Industry
02837679 Aarhus University Hospital Other
02837666 Universidad Autonoma de Ciudad Juarez Other
02837653 Universidad Autonoma de Madrid Other
02837640 Beirut Eye Specialist Hospital Other
我想找到最常见的主要赞助商。我可以使用以下方法列出每个组的大小:
df.groupby(['lead_sponsor', 'lead_sponsor_class']).size()
这就给了我:
lead_sponsor lead_sponsor_class
307 Hospital of PLA Other 1
3E Therapeutics Corporation Industry 1
3M Industry 4
4SC AG Industry 8
5 Santé Other 1
但我如何找到最常见的前10个群体呢?如果我这样做:
df.groupby(['lead_sponsor', 'lead_sponsor_class']).size().sort_values(ascending=False).head(10)
然后我得到一个错误:
AttributeError:“Series”对象没有“sort\u values”属性
我认为你可以使用:
在is注释中:
比.sort_值(升序=False)快。相对于序列对象大小的小n的头(n)
样本:
import pandas as pd
df = pd.DataFrame({'id': {0: 2837692, 1: 2837679, 2: 2837666, 3: 2837653, 4: 2837640},
'lead_sponsor': {0: 'a', 1: 'a', 2: 'a', 3: 's', 4: 's'},
'lead_sponsor_class': {0: 'Industry', 1: 'Other', 2: 'Other', 3: 'Other', 4: 'Other'}})
print (df)
id lead_sponsor lead_sponsor_class
0 2837692 a Industry
1 2837679 a Other
2 2837666 a Other
3 2837653 s Other
4 2837640 s Other
print (df.groupby(['lead_sponsor', 'lead_sponsor_class']).size())
lead_sponsor lead_sponsor_class
a Industry 1
Other 2
s Other 2
dtype: int64
print (df.groupby(['lead_sponsor', 'lead_sponsor_class']).size().sort_values(ascending=False).head(2))
lead_sponsor lead_sponsor_class
s Other 2
a Other 2
dtype: int64
print (df.groupby(['lead_sponsor', 'lead_sponsor_class']).size().nlargest(2))
lead_sponsor lead_sponsor_class
a Other 2
s Other 2
dtype: int64
对我来说,你的解决方案也很有效。我明白这是调用
.size()
a系列的结果吗?我想我很困惑,因为它看起来像一个数据帧,而不是一个系列(它将两列打印到左边的方式)。是的,它是series
。您可以通过打印(键入(df.groupby(['lead\u-shandor','lead\u-shandor\u-class']).size())来测试它。
import pandas as pd
df = pd.DataFrame({'id': {0: 2837692, 1: 2837679, 2: 2837666, 3: 2837653, 4: 2837640},
'lead_sponsor': {0: 'a', 1: 'a', 2: 'a', 3: 's', 4: 's'},
'lead_sponsor_class': {0: 'Industry', 1: 'Other', 2: 'Other', 3: 'Other', 4: 'Other'}})
print (df)
id lead_sponsor lead_sponsor_class
0 2837692 a Industry
1 2837679 a Other
2 2837666 a Other
3 2837653 s Other
4 2837640 s Other
print (df.groupby(['lead_sponsor', 'lead_sponsor_class']).size())
lead_sponsor lead_sponsor_class
a Industry 1
Other 2
s Other 2
dtype: int64
print (df.groupby(['lead_sponsor', 'lead_sponsor_class']).size().sort_values(ascending=False).head(2))
lead_sponsor lead_sponsor_class
s Other 2
a Other 2
dtype: int64
print (df.groupby(['lead_sponsor', 'lead_sponsor_class']).size().nlargest(2))
lead_sponsor lead_sponsor_class
a Other 2
s Other 2
dtype: int64