import pandas as pd
import matplotlib.pyplot as plt
from scipy.stats import linregress
if __name__ == '__main__':
    pd.options.display.max_columns = 999
    sales = pd.read_excel("C:/Users/18124/Desktop/pandas/024_线性回归_数据预测/Sales.xlsx", dtype={"Month":str})
    print(sales.head())
    slope, intercept, r, p, std_err = linregress(sales.index, sales.Revenue)
    exp = sales.index * slope + intercept
    plt.scatter(sales.index, sales.Revenue)
    plt.plot(sales.index, exp, color = "orange")
    # 预测2019年12月
    print(slope*35+intercept)
    plt.title(f"y = {slope}*x+{intercept}")
    plt.xticks(sales.index, sales.Month, rotation=90)
    plt.tight_layout()
    plt.show()
    # 画趋势线