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：

L8-1%MeOH  85.00-10.00 Ramp 2
Temperature	Abs
84.97000122	0.289775699
84.73000336	0.289772898
84.51999664	0.289753914
84.30999756	0.289791703
84.12000275	0.289888173
83.91999817	0.289871931
83.72000122	0.289892614
83.51999664	0.289982051
83.31999969	0.289918751
83.12000275	0.289979219
82.91999817	0.290063828
82.72000122	0.290138334
82.51999664	0.290162265
82.31999969	0.290249765
82.12000275	0.290316135
81.91999817	0.290309072
81.72000122	0.290509135
81.51999664	0.290560335
81.31999969	0.290631235
81.12000275	0.290638924
80.91999817	0.290659249
80.76999664	0.290761203
80.51999664	0.290816337
80.31999969	0.290902913
80.12000275	0.290874779
79.91999817	0.291025519
79.72000122	0.291229129
79.54000092	0.291381031
79.31999969	0.291313767
79.12000275	0.291418821
78.91999817	0.291318715
78.76999664	0.291283578
78.47000122	0.291214496
78.31999969	0.291229159
78.12000275	0.291251034
77.91000366	0.291236848
77.72000122	0.291296125
77.51999664	0.291178763
77.31999969	0.291171879
77.12000275	0.291263372
76.91999817	0.291264534
76.73000336	0.291292548
76.51999664	0.291220725
76.31999969	0.291292846
76.13999939	0.291277051
75.91999817	0.291291118
75.72000122	0.29129523
75.54000092	0.291274279
75.37000275	0.29128772
75.12000275	0.291312903
74.94000244	0.291347712
74.76999664	0.29123205
74.51999664	0.291254818
74.31999969	0.291262716
74.12000275	0.291325003
73.91999817	0.291266918
73.72000122	0.291336954
73.51999664	0.29133147
73.31999969	0.291346252
73.16999817	0.291326523
72.91999817	0.291337758
72.72000122	0.291334778
72.51999664	0.291236609
72.31999969	0.291340023
72.12000275	0.291321546
71.91999817	0.291348487
71.76999664	0.291358143
71.51999664	0.291290313
71.37000275	0.291313708
71.12000275	0.291264296
70.91999817	0.291350961
70.72000122	0.29136616
70.51999664	0.291316688
70.31999969	0.29128924
70.12000275	0.291255236
69.91999817	0.291306883
69.72000122	0.291192532
69.51999664	0.291173846
69.31999969	0.291179359
69.12000275	0.291233063
68.97000122	0.291287482
68.72000122	0.291226387
68.51999664	0.291262358
68.31999969	0.29126206
68.16999817	0.291240603
67.91999817	0.291168541
67.76999664	0.291122228
67.54000092	0.291165233
67.37000275	0.291113824
67.12000275	0.291047186
66.91999817	0.29107511
66.72000122	0.291123986
66.51999664	0.291230887
66.31999969	0.291136354
66.12000275	0.291114628
65.91999817	0.291155487
65.72000122	0.291145295
65.51999664	0.291066349
65.37000275	0.291025281
65.12000275	0.290942103
64.91999817	0.291067541
64.72000122	0.291023403
64.51999664	0.291036457
64.31999969	0.290963501
64.12000275	0.290956467
63.91999817	0.290989757
63.72000122	0.290984869
63.52000046	0.290999979
63.34000015	0.290966332
63.11999893	0.290926278
62.91999817	0.29093352
62.72000122	0.290865094
62.52000046	0.290893644
62.31999969	0.290822715
62.16999817	0.290895939
61.91999817	0.290778458
61.74000168	0.290800095
61.52000046	0.290780872
61.31999969	0.29076016
61.11999893	0.290794849
60.91999817	0.290686935
60.72000122	0.290691435
60.52000046	0.290566146
60.36999893	0.290671319
60.11999893	0.290581554
59.91999817	0.29061988
59.72000122	0.290570319
59.52000046	0.290494889
59.31999969	0.29041636
59.11999893	0.290560424
58.91999817	0.290550739
58.72000122	0.29045558
58.54000092	0.290323019
58.31999969	0.290423036
58.11999893	0.290393472
57.93999863	0.290405154
57.72000122	0.290409893
57.52000046	0.290291041
57.31999969	0.2904208
57.11999893	0.290308923
56.91999817	0.290231735
56.74000168	0.290227145
56.56999969	0.290249825
56.33000183	0.290192008
56.16999817	0.29016766
55.91999817	0.290216953
55.72999954	0.290187359
55.52000046	0.290102571
55.31999969	0.290104598
55.15000153	0.290063471
54.91999817	0.289918304
54.72000122	0.289920121
54.52000046	0.289979011
54.36999893	0.289980888
54.11999893	0.289954096
53.91999817	0.28988874
53.72000122	0.28974846
53.52000046	0.289820552
53.31999969	0.289742619
53.11999893	0.289817274
52.93999863	0.28978923
52.72000122	0.289813191
52.52000046	0.289613396
52.31999969	0.289732784
52.16999817	0.289775223
51.91999817	0.289646894
51.77000046	0.289596826
51.52000046	0.28956914
51.31999969	0.289584905
51.11999893	0.289490074
50.91999817	0.289438248
50.72000122	0.289477974
50.52000046	0.289325744
50.31999969	0.289276809
50.11999893	0.289331555
49.91999817	0.289295018
49.72000122	0.289296627
49.52000046	0.28915143
49.31999969	0.289193183
49.11999893	0.289128959
48.91999817	0.289065033
48.72000122	0.289002121
48.52000046	0.289101541
48.31999969	0.289002627
48.11999893	0.28890878
47.91999817	0.289007485
47.72000122	0.288935453
47.52000046	0.288857132
47.27000046	0.288808048
47.11999893	0.288675219
46.91999817	0.288865328
46.72000122	0.288711906
46.52000046	0.288633972
46.31999969	0.28860575
46.15000153	0.28852132
45.91999817	0.288538575
45.66999817	0.288431108
45.52999878	0.288401216
45.31999969	0.288309574
45.11999893	0.288317353
44.91999817	0.288279504
44.72000122	0.288180709
44.54999924	0.288055897
44.31999969	0.288086653
44.11999893	0.28794685
43.91999817	0.287966996
43.72000122	0.287874937
43.52000046	0.287852168
43.36999893	0.287828118
43.11999893	0.287792981
42.91999817	0.287585467
42.72999954	0.287576437
42.52000046	0.287577331
42.31999969	0.287411392
42.11999893	0.28738001
41.91999817	0.287313342
41.72000122	0.287242383
41.54000092	0.287164331
41.31999969	0.287036091
41.11999893	0.28703624
40.91999817	0.286783516
40.77000046	0.286710471
40.52000046	0.286570787
40.31999969	0.28652817
40.11999893	0.286334992
39.91999817	0.286312372
39.72000122	0.286121011
39.52999878	0.286084503
39.31999969	0.285883009
39.11999893	0.285734564
38.91999817	0.285749257
38.72000122	0.285529494
38.56999969	0.28531602
38.31999969	0.285131425
38.11999893	0.284954608
37.91999817	0.284751147
37.72000122	0.284648031
37.52999878	0.284379751
37.31999969	0.284210891
37.11999893	0.284112632
36.91999817	0.283857942
36.72000122	0.283601731
36.54000092	0.283411682
36.31999969	0.283199817
36.11999893	0.282873571
35.86999893	0.282679051
35.72000122	0.282400459
35.52000046	0.282109261
35.31999969	0.281829298
35.11999893	0.281520426
34.91999817	0.281252295
34.72000122	0.280893564
34.52999878	0.280569941
34.31999969	0.280233234
34.11999893	0.27978155
33.91999817	0.27933985
33.72000122	0.278997123
33.52000046	0.27866739
33.36999893	0.278179318
33.11999893	0.277876556
32.91999817	0.277383536
32.72000122	0.277005196
32.52000046	0.276473284
32.31999969	0.276106566
32.11999893	0.275604546
31.92000008	0.275117368
31.71999931	0.274595618
31.52000046	0.274127632
31.34000015	0.273532987
31.12000084	0.272938997
30.92000008	0.2725676
30.71999931	0.271897912
30.52000046	0.271363765
30.31999969	0.270751566
30.12000084	0.270129323
29.92000008	0.269645751
29.71999931	0.269051194
29.52000046	0.268456399
29.31999969	0.267962068
29.12000084	0.267270446
28.92000008	0.266738862
28.71999931	0.266006351
28.52000046	0.265481979
28.31999969	0.264831275
28.12000084	0.264232904
27.92000008	0.263675451
27.71999931	0.26303494
27.52000046	0.262438268
27.31999969	0.261804164
27.12000084	0.261120498
26.92000008	0.260569006
26.71999931	0.260044336
26.52000046	0.259405434
26.31999969	0.258819312
26.12000084	0.258242279
25.92000008	0.257679939
25.71999931	0.2570979
25.52000046	0.256487757
25.37000084	0.25590229
25.12000084	0.25532794
24.92000008	0.254778177
24.71999931	0.25410524
24.52000046	0.253657639
24.31999969	0.253173351
24.12000084	0.252608061
23.94000053	0.252033025
23.71999931	0.251483679
23.52000046	0.250937939
23.34000015	0.250526547
23.12000084	0.249979004
22.92000008	0.249466568
22.73999977	0.249063507
22.52000046	0.248660624
22.31999969	0.248175144
22.12000084	0.247794017
21.92000008	0.247374252
21.75	0.246980786
21.56999969	0.246683523
21.31999969	0.24631466
21.12000084	0.245911688
20.92000008	0.245679408
20.71999931	0.245338857
20.52000046	0.244930774
20.31999969	0.244685143
20.13999939	0.244306162
19.92000008	0.244005546
19.77000046	0.243800476
19.56999969	0.243406251
19.31999969	0.243300855
19.12000084	0.242946893
18.92000008	0.242748469
18.71999931	0.24243106
18.52000046	0.242171213
18.31999969	0.242056981
18.17000008	0.241781354
17.92000008	0.241629571
17.71999931	0.241456255
17.52000046	0.241409719
17.31999969	0.241192609
17.12000084	0.241008878
16.92000008	0.241027594
16.71999931	0.240784839
16.54999924	0.240591735
16.31999969	0.240471795
16.12000084	0.240396723
15.92000008	0.240146056
15.72000027	0.239994839
15.52000046	0.239879593
15.31999969	0.239714086
15.17000008	0.239571378
14.92000008	0.239323914
14.72000027	0.239161804
14.53999996	0.239066809
14.31999969	0.238902196
14.11999989	0.238841713
13.92000008	0.238734812
13.72000027	0.238687903
13.52000046	0.238492489
13.31999969	0.238415703
13.11999989	0.238240093
12.94999981	0.238196448
12.72000027	0.238090068
12.52000046	0.237997413
12.31999969	0.237959802
12.11999989	0.237707168
11.92000008	0.237703905
11.72000027	0.23764579
11.52000046	0.237563506
11.31999969	0.237518922
11.11999989	0.237495348
10.92000008	0.237405315
10.72000027	0.23731786
10.52000046	0.237466857
10.31999969	0.237433851
10.17000008	0.237485856
9.920000076	0.237137243