import numpy as np
import pandas as pd
from sklearn.linear_model import LinearRegression
import matplotlib.pyplot as plt
# 数据准备
data = {
'Year': [2019, 2020, 2021, 2022, 2023],
'Cat': [4412, 4862, 5806, 6536, 6980], # 宠物猫数量(单位:万只)
'Dog': [5503, 5222, 5429, 5119, 5175] # 宠物狗数量(单位:万只)
}
df = pd.DataFrame(data)
# 特征和目标变量
X = df['Year'].values.reshape(-1, 1) # 特征:年份
y_cat = df['Cat'].values # 宠物猫数量
y_dog