Python 基于条件从数据帧中删除值
有必要强调的是,这与删除行无关 在一个简单的例子中,我有一个来自传感器的文件:Python 基于条件从数据帧中删除值,python,pandas,dataframe,Python,Pandas,Dataframe,有必要强调的是,这与删除行无关 在一个简单的例子中,我有一个来自传感器的文件: import pandas as pd df = pd.DataFrame({'Date': ['15/03/2019 10:00:11.000', '15/03/2019 10:00:12.000' , '15/03/2019 10:00:13.000'], 'Pressure' : [-0.162, -0.162, 1.456], 'Conductivity': [-0.001, -0.001, 7.45],
import pandas as pd
df = pd.DataFrame({'Date': ['15/03/2019 10:00:11.000', '15/03/2019 10:00:12.000' , '15/03/2019 10:00:13.000'],
'Pressure' : [-0.162, -0.162, 1.456],
'Conductivity': [-0.001, -0.001, 7.45],
'Water_Temperature': [7.555, 7.555, 8.22],
'Water_Salinity': [0.004, 0.004, 7.63]})
我需要删除行中的值,其中'Pressure'用于设置所有列,而不首先按条件选择:
df.iloc[:, 1:] = df.iloc[:, 1:].mask(df['Pressure'] < 1)
print (df)
Date Pressure Conductivity Water_Temperature \
0 15/03/2019 10:00:11.000 NaN NaN NaN
1 15/03/2019 10:00:12.000 NaN NaN NaN
2 15/03/2019 10:00:13.000 1.456 7.45 8.22
Water_Salinity
0 NaN
1 NaN
2 7.63
df.iloc[:,1:]=df.iloc[:,1:].mask(df['Pressure']<1)
打印(df)
日期压力电导率水温\
2019年3月15日10:00:11.000楠
2019年3月15日10:00:12.000楠
2 15/03/2019 10:00:13.000 1.456 7.45 8.22
水和盐度
0南
1楠
2 7.63
如果确实需要空空间-获取带字符串的混合数值,则所有数值操作均失败:
df.iloc[:, 1:] = df.iloc[:, 1:].mask(df['Pressure'] < 1, '')
print (df)
Date Pressure Conductivity Water_Temperature \
0 15/03/2019 10:00:11.000
1 15/03/2019 10:00:12.000
2 15/03/2019 10:00:13.000 1.456 7.45 8.22
Water_Salinity
0
1
2 7.63
df.iloc[:,1:]=df.iloc[:,1:].mask(df['Pressure']<1',)
打印(df)
日期压力电导率水温\
0 15/03/2019 10:00:11.000
1 15/03/2019 10:00:12.000
2 15/03/2019 10:00:13.000 1.456 7.45 8.22
水和盐度
0
1.
2 7.63
df.iloc[:, 1:] = df.iloc[:, 1:].mask(df['Pressure'] < 1)
print (df)
Date Pressure Conductivity Water_Temperature \
0 15/03/2019 10:00:11.000 NaN NaN NaN
1 15/03/2019 10:00:12.000 NaN NaN NaN
2 15/03/2019 10:00:13.000 1.456 7.45 8.22
Water_Salinity
0 NaN
1 NaN
2 7.63
df.iloc[:, 1:] = df.iloc[:, 1:].mask(df['Pressure'] < 1, '')
print (df)
Date Pressure Conductivity Water_Temperature \
0 15/03/2019 10:00:11.000
1 15/03/2019 10:00:12.000
2 15/03/2019 10:00:13.000 1.456 7.45 8.22
Water_Salinity
0
1
2 7.63