python-3.x - 去除异常值

Question

我尝试使用我创建的以下函数删除异常值，但使用它后我得到了奇怪的值。我删除异常值的方法是否正确？

def remove_outliers(df,numeric_features):
'''
remove_outliers is a function which removes outliers by removing any
point above the mean by 2 standard deviations or below the mean by 2 standard deviations
df is the dataframe which the outliers are to be removed from
numeric_features are the numeric columns which might contain outliers
return new data frame
'''

#Iterate all the columns in numeric features
for col in numeric_features:

    mean = df[col].mean() #Find mean of column
    std = np.std(df[col],axis = 0)#find standard deviation of column

    #Variables used to find outliers
    above_outliers = mean + 2*std
    below_outliers = mean - 2*std

    outlier_indexes = df[col].loc[lambda x: (x>=above_outliers)|(x<=below_outliers)]

    #drop outliers from the dataframe column
    df= df.drop(outlier_indexes.index)
return df

标签： python-3.xpandas

Answer 1

尝试如下

  df1=  df[(df['col']>=below_outliers)&(df['col']<=above_outliers))