chapter2_1.m

来自「MABLAB学习资料」· M 代码 · 共 35 行

clear all
close all
clc

x1 = [1	 2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20];
y0 = [16	32	70	142 	260 	436 	682	 1010	1432	1960	2606	3382	4300	5372	6610	8026	9632	11440	13462	15710];
%y0 = [16	32	70	142 	265 	436 	680	 1010	1432	1960	2606	3382	4300	5372	6610	8026	9000	11440	13432	15700];

figure
plot(x1,y0,'r*')

p1 = polyfit(x1,y0,1)   			%一阶拟合  
y1 = polyval(p1,x1)
hold on
plot(x1,y1,'r-')

p2 = polyfit(x1,y0,2)   			%二阶拟合  
y2 = polyval(p2,x1)
hold on
plot(x1,y2,'b-')

p3 = polyfit(x1,y0,3)   			%三阶拟合  
y3 = polyval(p3,x1)
hold on
plot(x1,y3,'m-')

p4 = polyfit(x1,y0,4)   			%四阶拟合  
y4 = polyval(p4,x1)
hold on
plot(x1,y4,'g-')
xlabel('温度(摄氏度)')
ylabel('蒸发速度(ml/h)')
legend('data','一阶拟和','二阶拟和','三阶拟和','四阶拟和')