import numpy as np
import pandas as pd
from pyecharts.charts import Line
from pyecharts import options as opts
from matplotlib import pyplot as plt
import xlrd
# 读取 csv 文件
data = pd.read_excel('F:/LJX/lc8.xls')

# 假设 csv 文件中有两列数据：'x' 和 'y'
x_values = data['Temperature']
y_values = data['Abs']
plt.rcParams['font.sans-serif'] = ['SimHei']  # 用来正常显示中文标签
plt.rcParams['axes.unicode_minus'] = False  # 用来正常显示负号
plt.plot(x_values, y_values)
plt.xlabel("Temperature",size=14)
plt.ylabel("Abs",size=14)
plt.title("R8折线图",fontdict=None,loc="left",pad=None)
dy_dx = abs(np.diff(y_values) / np.diff(x_values))
print(type(dy_dx))
dy_dx_list = dy_dx.tolist()
print(type(dy_dx_list))
max_dao = dy_dx_list.index(max(dy_dx_list))
print(max_dao)
textprint = '导数最大值：' + str(dy_dx_list[max_dao]) +'。温度为：'+str(x_values[max_dao])
plt.annotate(textprint, xy=(x_values[max_dao],y_values[max_dao]), xytext=(x_values[max_dao],y_values[max_dao]-0.010), arrowprops=dict(arrowstyle="->"))
plt.show()

# # 创建折线图对象
# line_chart = Line()
#
# # 添加数据
# line_chart.add_xaxis(x_values.tolist())
# line_chart.add_yaxis('折线', y_values.tolist())
#
# # 设置全局配置
# line_chart.set_global_opts(
#     title_opts=opts.TitleOpts(title="black折线图"),
#     xaxis_opts=opts.AxisOpts(name='Temperature'),
#     yaxis_opts=opts.AxisOpts(name='Abs')
# )
#
# # 渲染生成 HTML 文件
# line_chart.render('black.html')

 数据如下：绘图也如下：