pandas库基础例题

Series创建及其打印，连接，删除

import pandas as pd

a = pd.Series([1,2,3,4,5])#用一维数组创建Series

b = pd.Series({
    
    'longitude':39,'latitude':116,'temperature':26})#用字典创建Series

#打印
print(a)
print("\n")

print(b)
print("\n")
#连接
c = a.append(b)
print(c)
print("\n")

#删除
d = b.drop("longitude")
print(d)

DataFrame的创建与行列访问

import pandas as pd
#字典构造DataFrame
df = pd.DataFrame({
    
    "name":"Alice","age":15,"friends":["bob","cindy","david"]})
print(df)
print("\n")

#数组创建DataFrame
df2 = pd.DataFrame([[1,2,1.5],[5,1.9,7],[-8,2,0.2],[9,6,3]],columns = ["t1","t2","t3"])
print(df2)
print("\n")

#列访问
print(df2["t1"])
print("\n")

#行访问
print(df2[0:3])
print("\n")

#行列访问（像二维数组，不过先列下标后行下标）
print(df2["t1"][0])
print("\n")

#修改
df2["t1"][0] = 2
print(df2["t1"][0])#若列索引不存在，则会直接新加一列

DataFrame使用dropna与fillna处理非数

#非数处理
import pandas as pd
a = pd.DataFrame([[1,2,3],[66,25,10,5],[-8,1,65,99,4]])
print(a)
print("\n")

#dropna丢弃有NAN的行或列
print(a.dropna(axis=0))
print("\n")
print(a.dropna(axis=1))
print("\n")

#fillna填充NAN
print(a.fillna(0))
print("\n")