如何在 Pandas Dataframe 中查找特定值
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How to find Specific values in Pandas Dataframe
提问by Shelly
I have imported the data in csv format in pandas. Can anybody tell me how i can find the values above 280 in one of the columns that i have and put them into another data frame. I have done the below code so far:
我已经将 csv 格式的数据导入到了Pandas中。谁能告诉我如何在我拥有的一列中找到 280 以上的值并将它们放入另一个数据框中。到目前为止，我已经完成了以下代码：
import numpy as np
import pandas as pd
df = pd.read_csv('...csv')
And the part of data is like the attached pic:enter image description here
部分数据如附图所示：在此处输入图片描述
回答by jezrael
You need boolean indexing:
你需要boolean indexing：
df1 = df[df[2] > 280]
If need select also only column add loc:
如果需要也只选择列添加loc：
s = df.loc[df[2] > 280, 2]
Sample:
样本：
df = pd.DataFrame({0:[1,2,3],
1:[4,5,6],
2:[107,800,300],
3:[1,3,5]})
print (df)
0 1 2 3
0 1 4 107 1
1 2 5 800 3
2 3 6 300 5
df1 = df[df[2] > 280]
print (df1)
0 1 2 3
1 2 5 800 3
2 3 6 300 5
s = df.loc[df[2] > 280, 2]
print (s)
1 800
2 300
Name: 2, dtype: int64
#one column df
df2 = df.loc[df[2] > 280, [2]]
print (df2)
2
1 800
2 300
