目前我有一个看起来像这样的表
ID Previous_Injuries Currently_Injured Injury_Type
1 Nan 0 Nan
1 Nan 1 Ankle
1 Nan 0 Nan
1 Nan 1 Wrist
1 Nan 0 Nan
1 Nan 1 Leg
1 Nan 0 Nan
2 Nan 1 Leg
2 Nan 0 Nan
我想添加到以前的伤害列并使我的表格看起来像这样:
ID Previous_Injuries Currently_Injured Injury_Type
1 Nan 0 Nan
1 Nan 1 Ankle
1 [Ankle] 0 Nan
1 [Ankle] 1 Wrist
1 [Ankle,Wrist] 0 Nan
1 [Ankle,Wrist] 1 Leg
1 [Ankle,Wrist,Leg] 0 Nan
2 Nan 1 Leg
2 [Leg] 0 Nan
如何在 pandas 中实现这种专栏？最好以列表的形式来做吗？
谢谢!
请您参考如下方法:
我们可以用cumsum做shift，然后split字符串，注意这里你使用的是Nan (string type) ，不是np.nan
s=df.Injury_Type.shift().fillna('Nan').add(',').cumsum().str[:-1].str.split(',')
df['new']=[[y for y in x if y != 'Nan'] for x in s ]
df
Out[322]:
ID Previous_Injuries Currently_Injured Injury_Type new
0 1 Nan 0 Nan []
1 1 Nan 1 Ankle []
2 1 Nan 0 Nan [Ankle]
3 1 Nan 1 Wrist [Ankle]
4 1 Nan 0 Nan [Ankle, Wrist]
5 1 Nan 1 Leg [Ankle, Wrist]
6 1 Nan 0 Nan [Ankle, Wrist, Leg]
再换题!
l=[]
for name , dfx in df.groupby('ID'):
s = dfx.Injury_Type.shift().fillna('Nan').add(',').cumsum().str[:-1].str.split(',')
dfx['new'] = [[y for y in x if y != 'Nan'] for x in s]
l.append(dfx)
pd.concat(l)
