todo

爬虫：

import requests
import bs4

url="http://jyt.ln.gov.cn/"
resp=requests.get(url)
# print(resp.content)
# 树状结构的对象（dom ）
soup=bs4.BeautifulSoup(resp.content,'html.parser')
a=soup.select('ul.gov_list2>li>a')
for m in a:
    print(m.string)

excel的操作

1. 写：

import openpyxl


book=openpyxl.Workbook()
sheet=book['Sheet']
for i in range(1,100):
    cell=sheet.cell(i,1)
    cell.value=str(i)

book.save("book1.xlsx")

2. 读：

import openpyxl

book=openpyxl.load_workbook('book1.xlsx')
sheet=book.active
cell=sheet['c4']
cell=sheet.cell(4,3)
print(cell.value)
book.close()

数据可视化

import matplotlib.pyplot as ptl
import numpy

# 一张图变四张
fig,sub=ptl.subplots(2,2)

x=numpy.arange(0,2*numpy.pi)
x=numpy.linspace(0,2*numpy.pi,100)
y=numpy.sin(x)
sub[0,0].plot(x,y)

y=numpy.cos(x)
sub[0,1].scatter(x,y,s=1)

y=x
sub[1,1].plot(x,y)

x=numpy.linspace(-numpy.pi/2,numpy.pi/2,100)
y=numpy.tanh(x)
sub[1,0].plot(x,y)
ptl.grid()
ptl.savefig('num.jpg')
ptl.show()