用matlab画分段曲线y=0.3954x^3-0.1435x^4+0.0149x^5 x=0~7 当x=3.5时tga

y=0.3954x^3-0.1435x^4+0.0149x^5 x=0~7 当x=3.5时tga=1.1106

y=0.2961x^3-0.1106x^4+0.0117x^5 x=7~14 当x=10.5时tga=0.70021

y=0.06028x^3-0.00897x^4+0.000395x^5 x=14~30 当x=22时tga=1.1918

因为每一小段关于小段中点对称,所以tga表示每一中点的斜率

完全不怎么懂,拜托给完整的代码,

问答/270℃/2024-12-30 10:51:28

x1=0:0.1:7;

x2=7:0.1:14;

x3=14:0.1:30;

y1=0.3954.*x1.^3-0.1435.*x1.^4+0.0149.*x1.^5;

y2=0.2961.*x2.^3-0.1106.*x2.^4+0.0117.*x2.^5;

y3=0.06028.*x3.^3-0.00897.*x3.^4+0.000395.*x3.^5;

plot(x1,y1)

hold on

plot(x2,y2)

hold on

plot(x3,y3)