我需要找出相对于该列中某些值的列元素的比例。例如,在此表A中,我想找出关于该列{ id1 = x和id2 = z }的值的列 Metric 的比率。有人可以帮我吗?
例如:
表A
+-------+------+-------+
| id1 | id2 | metric|
+-------+------+-------+
| x | z | 100 |
| x | w | 10 |
+-------+------+-------+
正确的结果:
表B
+-------+------+-------+-------+
| id1 | id2 | metric| result|
+-------+------+-------+-------+
| x | z | 100 | 1 | (100/100)
| x | w | 10 | 0.1 | (10/100)
+-------+------+-------+-------+
代码:
d = {'id1': ['x', 'x'], 'id2': ['z','w'], 'metric': [100,10] }
df = pd.DataFrame(data=d)
df
答案 0 :(得分:2)
如果我对您的理解正确,则说明以下内容:
d = {'id1': ['x', 'x'], 'id2': ['z','w'], 'metric': [100,10] }
df = pd.DataFrame(data=d)
df
# Manually choose the value by which to scale the column 'metric'
scaler = df.loc[(df['id1'] == 'x') & (df['id2'] == 'z'), 'metric'].values
# Divide all 'metric' values by the above scaler value
df['result'] = df['metric'] / scaler
df
id1 id2 metric result
0 x z 100 1.0
1 x w 10 0.1