pandas 的各种操作

import numpy as np
import pandas as pd

a1=[]
for q in range(10):
    ar1=[q,q+1,q+2,q+3]
    a1.append(ar1)

n1=np.array(a1)
df1 = pd.DataFrame(n1,index=range(10), columns=["t1","t2","t3","t4"])
#添加数据
df1.loc[10]=[10,11,12,13]
print(df1)
#删除指定行
df1.drop(labels=2,inplace=True)
print(df1)
#改一个元素
df1.loc[9,"t1"]=2
print(df1)
#改一行
df1.loc[9]=[1,2,3,4]
print(df1)

#写入json
df1.to_json("data/1.json",orient="index")
#读取
df2=pd.read_json("data/1.json",orient="index")
print(df2)