python常用语法笔记

1.注释：

#单行注释

ctrl + / 多行注释

2.对csv文件进行读取

方法1：

import pandas as pd
import matplotlib.pyplot as plt
import numpy as np
import pywt
import csv
from pandas import DataFrame
df = pd.DataFrame(pd.read_csv(r'C:\Users\jiaodanyang\Desktop\PHM\data\diabetes.csv'))
data = []
data = df.loc[:,'preg']  #iloc是根据所在列的位置进行索引，loc是根据列名进行索引
print(data)

方法2：

path = r'C:\Users\jiaodanyang\Desktop\PHM\data\diabetes.csv'

data_input = []
csvFile = open(path,'r', newline='') # 设置newline，否则两行之间会空一行
reader= csv.reader(csvFile)
for item in reader:
    data_input.append(item)

print(data_input)

方法3：

with open(path,'r') as f:
    #1.创建阅读器对象
    reader = csv.reader(f)
    #2.读取文件第一行数据
    head_row=next(reader)
    print(head_row)

data_attribute = []
for item in head_row:
    data_attribute.append(item)

print(data_attribute)