ex3prob6.m

matlab讲义

P=[60,80,100,120,140,160,180];
V=[80,69.2,60,52,45,38.6,32.5];
dv=[1,1]; V0=[60,50];
%画草图
plot(V,P,'r+',V,P)
pause
%一次拟合
aa=polyfit(V,P,1);
P1=polyval(aa,V)
plot(V,P1,V,P,'r+')
pause
%二次拟合
aa=polyfit(V,P,2)
V2=80:-0.1:32.5;
P2=polyval(aa,V2);
plot(V2,P2,V,P,'r*')
dp=(2*aa(1)*V0+aa(2)).*dv
x=40:10:70;
W=quad('ex3fun6',40,70)