我得走了
pd.DataFrame([["A1" "B1", "C1", "P"],
["A2" "B2", "C2", "P"],
["A3" "B3", "C3", "P"]], columns=["col_a" "col_b", "col_c", "col_d"])
col_a col_b col_c col_d
A1 B1 C1 P
A2 B2 C2 P
A3 B3 C3 P
...
我需要的结果基本上是重复,并确保每一行出现时,列在列中都有pqr扩展
col_a col_b col_c col_d
A1 B1 C1 P
A1 B1 C1 Q
A1 B1 C1 R
A2 B2 C2 P
A2 B2 C2 Q
A2 B2 C2 R
A3 B3 C3 P
A3 B3 C3 Q
A3 B3 C3 R
...
到目前为止,我只知道:
new_df = pd.DataFrame(np.repeat(df.values, 3, axis=0), columns=df.columns)
这会导致这些值的重复,但列d不变
编辑:
现在我偶然发现了另一个需求,对于每个独特的a列和b列,我需要在d列中添加"S"
例如,导致:
col_a col_b col_c col_d
A1 B1 C1 P
A1 B1 C1 Q
A1 B1 C1 R
A1 B1 T S
A2 B2 C2 P
A2 B2 C2 Q
A2 B2 C2 R
A2 B2 T S
非常感谢你的帮助!