df数据表，表格信息如下：

frequency CTR name

0 13 0.437587 0234s3

1 16 0.891773 023dfr

2 1 0.963663 34s231

3 4 0.383442 a34d21

4 4 0.791725 ss034q

5 8 0.528895 34s231

6 10 0.568045 0234s3

7 19 0.925597 023dfr

提取 frequency字段取值为4，8，10的行信息，实现效果如下：

frequency CTR name

3 4 0.383442 a34d21

4 4 0.791725 ss034q

5 8 0.528895 34s231

6 10 0.568045 0234s3

参考答案：

np.random.seed(0)
df = pd.DataFrame({"frequency":np.random.randint(1,20,8)
              ,"CTR":np.random.uniform(0,1,8)
              ,"name":["0234s3","023dfr","34s231","a34d21","ss034q","34s231","0234s3","023dfr"]})

df[df.frequency.isin([4,8,10])]

结果示例：