matlab数学实验 第八章~第十章部分习题答案.docVIP

第八章 exercize 2 x=[480 500 380 1100 1100 490 230 250 300 510 1300]; y=[180 150 170 350 460 240 60 90 110 250 200]; plot(x,y,*) c=corrcoef(x,y)； exercize 7(1) a=1/sqrt(2*pi)% 被积函数的最大值 a = 0.3989 n=10000;x=rand(n,1);y=unifrnd(0,0.4,n,1); c1=y0;c2=yexp(-x.^2/2)/sqrt(2*pi); nc=sum(c1c2) nc = 8534 i=nc*0.4/n i = 0.3414 7(3) n=60000; y=rand(n,1); x=unifrnd(0,pi,n,1); z=rand(n,1); c1=ysin(x);c2=zexp(-x.^2-y.^2); nc=sum(c1c2),nc*pi/n nc = 6981 ans = 0.3655 第九章 exercize 3(1) x=linspace(0,2*pi,10); y=sin(x); xi=linspace(0,2*pi,50);yi=sin(xi); yi1=interp1(x,y,xi); yi2=interp1(x,y,xi,spline); plot(xi,yi1,r,xi,yi2,b,x,y,*) e1=norm(yi1-yi),e2=norm(yi2-yi) %均方误差 e1 = 0.3097 e2 = 0.0158 exercize 3(4) x=linspace(-2,2,10);y=exp(-x.^2); xi=linspace(-2,2,80); yi1=interp1(x,y,xi);yi2=interp1(x,y,xi,spline); yi=exp(-xi.^2); plot(xi,yi1,r,xi,yi2,g,x,y,*) e1=norm(yi1-yi),e2=norm(yi2-yi) e1 = 0.1518 e2 = 0.0069 exercize 12 y=[100 75 80 70 50 65 90 100 110 60]; x1=[1000 600 1200 500 300 400 1300 1100 1300 300]; x2=[5 7 6 6 8 7 5 4 3 9]; plot(x1,y,*) plot(x2,y,o) [b,bint,r,rint,stats]=regress(y,[ones(10,1),x1,x2]); b b = 111.6918 0.0143 -7.1882 y0=b(1)+b(2)*1000+b(3)*6 y0 = 82.8594 第十章 exercize 2 f=[5;4;8];A=[2 -1 0;5 3 0];b=[4;15]; Aeq=[1 2 1];Beq=6;lb=zeros(3,1); [x,feval]=linprog(f,A,b,Aeq,Beq,lb) Optimization terminated. x = 0.0000 3.0000 0.0000 feval = 12.0000 exercize 4 f=[-30;-40];A=[20 100;40 80;90 60]; b=[200;200;360]; [x,feval]=linprog(f,A,b,[],[],[0;0]) Optimization terminated. x = 3.5000 0.7500 feval = -135.0000 exercize 12 %目标函数 fmb.m function f=fmb(x) f=-x(1)*x(2)*x(3); A=[1 -2 -2;1 2 2];b=[0;72]; lb=[-inf;10;-inf];ub=[inf;20;inf]; Aeq=[1 -1 0];Beq=10; [x,feval]=fmincon(@fmb,[20,10,0],A,b,Aeq,Beq,lb,ub,[]) x = 22.5850 12.5850 12.1225 feval = -3.4456e+003