55 lines
640 B
Markdown
55 lines
640 B
Markdown
---
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id: 5e9a0a8e09c5df3cc3600ed4
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title: '访问与更改元素、行和列'
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challengeType: 11
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videoId: v-7Y7koJ_N0
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bilibiliIds:
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aid: 590517748
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bvid: BV1Eq4y1f7Fa
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cid: 409025392
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dashedName: accessing-and-changing-elements-rows-columns
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---
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# --question--
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## --text--
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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？
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```py
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a = np.array([[1, 2, 3, 4, 5], [6, 7, 8, 9, 10]])
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# Output:
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# [[ 1 2 20 4 5]
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# [ 6 7 20 9 10]]
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```
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## --answers--
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```python
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a[:, 3] = 20
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```
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---
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```python
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a[2, :] = 20
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```
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---
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```python
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a[:, 2] = 20
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```
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---
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```python
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a[1, 2] = 20
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```
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## --video-solution--
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3
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