freeCodeCamp/curriculum/challenges/chinese/08-data-analysis-with-python/numpy/accessing-and-changing-elements,-rows,-columns.md

id, title, challengeType, videoId, bilibiliIds, dashedName

id	title	challengeType	videoId	bilibiliIds	dashedName
5e9a0a8e09c5df3cc3600ed4	访问与更改元素、行和列	11	v-7Y7koJ_N0	aid bvid cid 590517748 BV1Eq4y1f7Fa 409025392	accessing-and-changing-elements-rows-columns

--question--

--text--

以下哪行代码将下面的 Numpy 数组的第三行的数值都更改成 20？

a = np.array([[1, 2, 3, 4, 5], [6, 7, 8, 9, 10]])

# Output:
# [[ 1  2  20  4  5]
# [ 6  7 20  9 10]]

--answers--

a[:, 3] = 20

---

a[2, :] = 20

---

a[:, 2] = 20

---

a[1, 2] = 20

--video-solution--

3