matlab中离散数拟合出函数方程x=30:5:310;y=[33.45 37.23 40.65 41.55 30.75 40.38 30.22 30.11 22.91 23.54 22.64 13.82 13 13.1 10.3 9.85 10.57 10.21 10.3 12.37 12.19 12.37 15.08 15.8 15.8 18.86 20.03 21.29 23.54 24.26 25.88 26.42 27.95 28.49 29
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/30 00:35:52
![matlab中离散数拟合出函数方程x=30:5:310;y=[33.45 37.23 40.65 41.55 30.75 40.38 30.22 30.11 22.91 23.54 22.64 13.82 13 13.1 10.3 9.85 10.57 10.21 10.3 12.37 12.19 12.37 15.08 15.8 15.8 18.86 20.03 21.29 23.54 24.26 25.88 26.42 27.95 28.49 29](/uploads/image/z/2685923-35-3.jpg?t=matlab%E4%B8%AD%E7%A6%BB%E6%95%A3%E6%95%B0%E6%8B%9F%E5%90%88%E5%87%BA%E5%87%BD%E6%95%B0%E6%96%B9%E7%A8%8Bx%3D30%3A5%3A310%3By%3D%5B33.45+37.23+40.65+41.55+30.75+40.38+30.22+30.11+22.91+23.54+22.64+13.82+13+13.1+10.3+9.85+10.57+10.21+10.3+12.37+12.19+12.37+15.08+15.8+15.8+18.86+20.03+21.29+23.54+24.26+25.88+26.42+27.95+28.49+29)
matlab中离散数拟合出函数方程x=30:5:310;y=[33.45 37.23 40.65 41.55 30.75 40.38 30.22 30.11 22.91 23.54 22.64 13.82 13 13.1 10.3 9.85 10.57 10.21 10.3 12.37 12.19 12.37 15.08 15.8 15.8 18.86 20.03 21.29 23.54 24.26 25.88 26.42 27.95 28.49 29
matlab中离散数拟合出函数方程
x=30:5:310;
y=[33.45 37.23 40.65 41.55 30.75 40.38 30.22 30.11 22.91 23.54 22.64 13.82 13 13.1 10.3 9.85 10.57 10.21 10.3 12.37 12.19 12.37 15.08 15.8 15.8 18.86 20.03 21.29 23.54 24.26 25.88 26.42 27.95 28.49 29.66 29.75 30.2 30.38 30.65 30.29 29.84 29.03 28.31 27.32 25.61 25.07 23.54 22.46 20.75 19.04 17.69 15.62 13.46 12.1 12.37 13.16 14 15.17 16.61];
这是我的x,y数,一共60个,想把这60个点的函数表达式求出来,可以用积分形式表示最好.
matlab中离散数拟合出函数方程x=30:5:310;y=[33.45 37.23 40.65 41.55 30.75 40.38 30.22 30.11 22.91 23.54 22.64 13.82 13 13.1 10.3 9.85 10.57 10.21 10.3 12.37 12.19 12.37 15.08 15.8 15.8 18.86 20.03 21.29 23.54 24.26 25.88 26.42 27.95 28.49 29
首先你给的题目有问题,Y只有59个数据,所以我给X多增加了2个.
其次你怎么没赏分
最后的结果是只有这样的人才会来解答你的问题了,
clear;clc;
x=30:5:320;
y=[33.45 37.23 40.65 41.55 30.75 40.38 30.22 30.11 22.91 23.54 22.64 13.82 13 13.1 10.3 9.85 10.57 10.21 10.3 12.37 12.19 12.37 15.08 15.8 15.8 18.86 20.03 21.29 23.54 24.26 25.88 26.42 27.95 28.49 29.66 29.75 30.2 30.38 30.65 30.29 29.84 29.03 28.31 27.32 25.61 25.07 23.54 22.46 20.75 19.04 17.69 15.62 13.46 12.1 12.37 13.16 14 15.17 16.61];
figure(1);
subplot(2,1,1);
plot(x,y,'o');%通过观察散点图发现有4个拐点,故用五次多项式拟合即可
aa=polyfit(x,y,5);
f_x=vpa(poly2sym(aa,'x'),4)
x=30:5:320;
subplot(2,1,2);
plot(x,polyval(aa,x),'r-o');
axis([0 350 0 50])
结果;
f_x =
.1393e-8*x^5-.1168e-5*x^4+.3437e-3*x^3-.4123e-1*x^2+1.675*x+17.55
其他结果自己运行看