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超强图解 Pandas，建议收藏
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超强图解 Pandas，建议收藏
2022-08-24 11:54:10
本文将借助可视化的过程，讲解Pandas的各种操作。一起来看一下吧。
Pandas是数据挖掘常见的工具，掌握使用过程中的函数是非常重要的。
sort_values
(dogs[dogs['size'] == 'medium']
.sort_values('type')
.groupby('type').median()
)执行步骤：
- size列筛选出部分行
- 然后将行的类型进行转换
- 按照type列进行分组，计算中位数
selecting a column
dogs['longevity']
groupby + mean
dogs.groupby('size').mean()执行步骤：
- 将数据按照size进行分组
- 在分组内进行聚合操作
grouping multiple columns
dogs.groupby(['type', 'size'])
groupby + multi aggregation
(dogs
.sort_values('size')
.groupby('size')['height']
.agg(['sum', 'mean', 'std'])
)- 按照size列对数据进行排序
- 按照size进行分组
- 对分组内的height进行计算
filtering for columns
df.loc[:, df.loc['two'] <= 20]
filtering for rows
dogs.loc[(dogs['size'] == 'medium') & (dogs['longevity'] > 12), 'breed']
dropping columns
dogs.drop(columns=['type'])
joining
ppl.join(dogs)
merging
ppl.merge(dogs, left_on='likes', right_on='breed', how='left')
pivot table
dogs.pivot_table(index='size', columns='kids', values='price')
melting
dogs.melt()
pivoting
dogs.pivot(index='size', columns='kids')
stacking column index
dogs.stack()
unstacking row index
dogs.unstack()
resetting index
dogs.reset_index()
setting index
dogs.set_index('breed')
责任编辑：庞桂玉
来源：
Python开发者
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