4.提取csv文件中满足要求的数据_python对csv数据提取某列的某些行

########提取csv文件中满足要求的数据##########
 
import numpy as np #
import pandas as pd 
import csv
 
# 1.打开csv文件
all_data=pd.read_csv('C:\\Users\\86178\\Desktop\\python\\pythonProject\\ethylene_methane.csv')
# 2.要求（满足Methane列中=0.0且满足Ethylene列中>0.0的数据 ）
some = all_data[(all_data['Methane conc (ppm)'] == 0.0) & (all_data['Ethylene conc (ppm)'] > 0.0)]
# 3.将满足要求的数据保存到Ethylene.csv文件中
df=pd.DataFrame(some)
df.to_csv('C:/Users/86178/Desktop/python/pythonProject/Ethylene.csv')