MATLAB线性拟合问题

elephant_

怎么把两个线拟合到一个图里，然后显示y轴标题为“电阻值”，x轴标题为“个数”

x=[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16];
; a) X: z! r0 ry1=[2.23,2.53,4.52,3.01,2.75,3.86,2.25,2.39,0.19,2.62,-4.68,-4.76,-10.75,-7.84,-5.25,-9.96];
! u: G' _7 q# G& H( s+ K! [/ jy2=[2.37,2.53,3.91,3.01,2.75,3.86,2.25,2.39,0.19,2.62,1.07,-4.76,-10.75,-7.84,-5.25,-9.96];
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figure(1);
- ?' D. k9 l) ~& L( e0 o%plot(x,y1,'r',x,y2,'b);
plot(x,y,'r');
title('线性拟合')
hold on;
; Z0 e7 u$ g4 n' w$ L( q! Z+ @[a,b]=Linear_fitting(x,y);

t=1:1:16;
$ }3 f! e+ ^: t7 y* k4 G$ Yz=a*t+b;
plot(t,z);

function [a,b]=Linear_fitting(x,y)
* P/ A- f. d+ T8 }5 s+ |n=size(x,2);
sum_xy=sum(x.*y);
1 y3 w. ^6 i: G# Gsum_x=sum(x);
sum_y=sum(y);
# f: \" A4 s% ~' Gsum_xx=sum(x.*x);

- Y$ b4 f4 E& ^- H# ga=(n*sum_xy-sum_x*sum_y)/(n*sum_xx-sum_x^2);
# ~' Q; ]. x" L# u# ^, Jb=(sum_xy-sum_xx*sum_y/sum_x)/(sum_x-n*sum_xx/sum_x);

end
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purpose_857

能否先给出一个你认为已达成目的的图呢，它长什么样子。

elephant_

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whatever_

你是要 这种效果吧？

拟合4次

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拟合2次

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测试例程

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