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”

# K) v- a% O& B: Wx=[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16];
8 t% d/ x) Y# s" i" Ly1=[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];
: F; R# y. Q8 oy2=[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];
% R8 r; i! M8 R8 l4 Y
figure(1);
%plot(x,y1,'r',x,y2,'b);
plot(x,y,'r');
+ {& W# `5 a. S# B8 _3 Ptitle('线性拟合')
- j- b8 f$ |8 u8 I8 T$ Vhold on;
[a,b]=Linear_fitting(x,y);

t=1:1:16;
8 q+ e! h9 J. |5 p9 f; mz=a*t+b;
% \. ^, r% }% g$ W: E, rplot(t,z);
" v! Q. v% ~( \3 E* \# @" ?) J
5 Q3 y$ Z; r% nfunction [a,b]=Linear_fitting(x,y)
n=size(x,2);
sum_xy=sum(x.*y);
' f' ^6 x7 P2 B' |7 @3 lsum_x=sum(x);
, s; t5 S/ S7 ]& M# k4 f: c3 msum_y=sum(y);
- D8 a. [3 i, N- wsum_xx=sum(x.*x);
7 ?, H: z+ ~  D# A; Z8 Q$ l
6 i! j6 h+ ~' i8 O% Ma=(n*sum_xy-sum_x*sum_y)/(n*sum_xx-sum_x^2);
b=(sum_xy-sum_xx*sum_y/sum_x)/(sum_x-n*sum_xx/sum_x);

3 _8 F) o( r+ ?" r; jend
- I2 \; R/ e5 |. G

whatever_

你是要 这种效果吧？

拟合4次

0 e( S; u* h8 @$ t1 o0 U. \& L& F2 _

拟合2次

测试例程

  ~- J* W; q: x- w+ w. b7 v. i9 l

elephant_

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。