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75 lines
1.3 KiB
Markdown
75 lines
1.3 KiB
Markdown
---
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id: 5e9a093a74c4063ca6f7c15e
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title: DataFrames 中的数据清理
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challengeType: 11
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videoId: sTMN_pdI6S0
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bilibiliIds:
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aid: 505597026
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bvid: BV1Yg411c7bx
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cid: 409018948
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dashedName: data-cleaning-with-dataframes
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---
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# --description--
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*在视频中我们使用的编辑器工具是在 notebook.ai 这个平台，你也可以选择用其他的平台，比如说 Google Colab 也是一个不错的选择。*
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以下有更多的资料：
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- <a href="https://github.com/ine-rmotr-curriculum/data-cleaning-rmotr-freecodecamp" target="_blank" rel="noopener noreferrer nofollow">在 GitHub 平台的 Notebooks</a>
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- <a href="https://colab.research.google.com/github/googlecolab/colabtools/blob/master/notebooks/colab-github-demo.ipynb" target="_blank" rel="noopener noreferrer nofollow">如何使用 Google Colab 来打开 GitHub 上的 Notebooks</a>
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# --question--
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## --text--
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以下代码会打印出什么？
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```py
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import pandas as pd
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import numpy as np
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s = pd.Series([np.nan, 1, 2, np.nan, 3])
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s = s.fillna(method='ffill')
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print(s)
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```
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## --answers--
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<pre>
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0 1.0
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1 1.0
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2 2.0
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3 3.0
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4 3.0
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dtype: float64
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</pre>
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---
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<pre>
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0 NaN
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1 1.0
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2 2.0
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3 2.0
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4 3.0
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dtype: float64
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</pre>
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---
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<pre>
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0 NaN
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1 1.0
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2 2.0
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3 NaN
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4 3.0
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dtype: float64
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</pre>
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## --video-solution--
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2
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