如何使用Pandas上列表中的值随机替换列中的值？

Question

我有以下数据帧：

data = {'Names':['Antonio','Bianca','Chad','Damien','Edward','Frances','George'],'Sport':['Basketball','Placeholder','Football','Placeholder','Tennis','Placeholder','Placeholder']}

df = pd.DataFrame(data, columns = ['Names','Sport'])

我想用以下列表中的任意值随机替换值“占位符”：

extra_sports = ['Football','Basketball','Tennis','Rowing']

最终结果应该是这样的，即值“占位符”现在消失，并随机替换为列表中的值：

data = {'Names':['Antonio','Bianca','Chad','Damien','Edward','Frances','George'],'Sport':['Basketball','Tennis','Football','Rowing','Tennis','Football','Tennis']}

df = pd.DataFrame(data, columns = ['Names','Sport'])

如果可能的话，我将如何实现random.seed，以便复制结果

Answer 1

我相信您只需要将值Placeholder替换为list，对于list的长度，请使用sum的布尔值True来替换受益数组的正确长度：

extra_sports = ['Football','Basketball','Tennis','Rowing']
   
np.random.seed(1) 
m = df['Sport'].eq('Placeholder')
df.loc[m, 'Sport'] = np.random.choice(extra_sports, size=m.sum())
print (df)
     Names       Sport
0  Antonio  Basketball
1   Bianca  Basketball
2     Chad    Football
3   Damien      Rowing
4   Edward      Tennis
5  Frances    Football
6   George    Football