matlab7.X课后习题.doc

第二章第三题clc;clear;close alla=5-round(100*rand(50,2)/10a = -4.5000 3.1000 2.7000 -1.8000 -1.1000 2.0000 0.1000 -0.4000 -3.9000 3.5000 -2.6000 -2.0000 0.4000 1.2000 4.8000 -3.6000 -3.2000 -3.5000 0.6000 -0.9000 -1.2000 0 -2.9000 -4.0000 -4.2000 -3.2000 -2.4000 -1.4000 3.2000 -3.2000 0.9000 -1.6000 -4.4000 1.6000 -4.2000 2.1000 0.9000 1.6000 -3.9000 -0.3000 4.4000 -2.3000 1.5000 1.9000 -3.1000 -3.4000 4.9000 -0.7000 3.6000 1.3000 3.0000 -2.0000 3.0000 -0.5000 -1.0000 0.6000 2.3000 -1.9000 3.0000 -1.2000 4.8000 -2.9000 -2.5000 -4.6000 0.5000 -0.2000 -4.3000 -3.8000 0.3000 3.3000 0.8000 -4.8000 -3.5000 2.3000 -0.3000 2.5000 3.0000 -3.8000 -1.7000 -2.4000 -3.4000 3.6000 4.8000 4.9000 -1.8000 -3.9000 1.2000 3.0000 -3.3000 2.0000 0 -1.6000 -2.1000 2.2000 0.7000 0.3000 2.0000 4.40003.1000 -4.9000第六题clc;clear;close alla=randn(10,10)b=find(-0.5a=10 if rem(y,10)=0 i=i+1; end y=fix(y/10); endenddisp(i) 504第五题clc;clear;close alli=1x1=-3:0.01:3;for x=x1 if x=-3&x=-1&x=1&x40 bonus=(number-40)*0.01+20*0.02+10*0.05+10*0.1;elseif number20 bonus=(number-20)*0.02+10*0.05+10*0.1;elseif number10 bonus=(number-10)*0.05+10*0.1;else bonus=number*0.1;endData=sprintf(the bonus is %d,bonus);disp(Data);input the profit150000the bonus is 1.501500e+003第九题clc;clear;close allm=1;n=2;for i=1:1:15 x(i)=n/m; k=n; n=m+n; m=k;endsum(x)ans = 24.5701第五章第一题clc;clear;close alla1=1 9 8;7 2 5;3 -2 7;b1=inv(a1)det(a1)a2=1 0 -7 5;0 -26 7 2;7 4 3 5;8 -3 2 15;b2=inv(a2)det(a2)b1 = -0.0543 0.1787 -0.0656 0.0769 0.0385 -0.1154 0.0452 -0.0656 0.1380ans = -442b2 = 0.1501 0.0654 0.3046 -0.1603 -0.0509 -0.0471 -0.0312 0.0336 -0.1697 -0.0204 -0.0703 0.0827 -0.0676 -0.0416 -0.1593 0.1478ans = -9334第二题clc;clear;close alla1=1 2 3;2 2 5;3 5 1;b1=11 12 31;x1=a1b1a2=3 1 0 5;0 6 7 3;0 4 3 0;2 -1 2 6;b2=2 4 7 8;x2=a2b2x1 = 1.8000 5.2000 -0.4000x2 = 28.1892 -9.4595 14.9459 -14.6216第八题clc;clear;close allp1=1 -2 -3 4 2;r1=roots(p1)p2=1 -7 5 31 -30;r2=roots(p2)p3=1 -1 -25 25;r3=roots(p3)p4=-2 3 1 5 8 0;r4=roots(p4)r1 = 2.4142 1.4142 -1.4142 -0.4142r2 = 5.0000 -2.0000 3.0000 1.0000r3 = -5.0000 5.0000 1.0000r4 = 0 2.4176 0.0148 + 1.3215i 0.0148 - 1.3215i -0.9473 第九题clc;clear;close allp1=1 -2 -3 4 2;y1=polyval(p1,-1.5 2.1 3.5)p2=1 -7 5 31 -30;y2=polyval(p2,-1.5 2.1 3.5)p3=1 -1 -25 25;y3=polyval(p3,-1.5 2.1 3.5)p4=-2 3 1 5 8 0;y4=polyval(p4,-1.5 2.1 3.5)y1 = 1.0625 -1.9039 43.5625y2 = -36.5625 11.7711 -10.3125y3 = 56.8750 -22.6490 -31.8750y4 = 26.2500 24.7733 -468.1250第十三题clc;clear;close alla1=rand(1,50);b1=max(a1)c1=min(a1)m1=mean(a1)s1=std(a1)2a2=randn(1,50);b2=max(a2)c2=min(a2)m2=mean(a2)s2=std(a2)2b1 = 0.9901c1 = 0.0150m1 = 0.5246s1 = 0.0646b2 = 1.4885c2 = -2.2023m2 = -0.2348s2 = 0.8153第十六题clc;clear;close allt=-2:.1:2;x1=sin(50*t)+randn(size(t);x2=cos(50*t)+randn(size(t);x3=sin(50*t)+randn(size(t);r1=corrcoef(x1,x2)r2=corrcoef(x1,x3)X1=randn(size(t);X2=randn(size(t);X3=randn(size(t);R1=corrcoef(X1,X2)R2=corrcoef(X1,X3)r1 = 1.0000 -0.0274 -0.0274 1.0000r2 = 1.0000 0.3374 0.3374 1.0000R1 = 1.0000 -0.0346 -0.0346 1.0000R2 = 1.0000 0.1118 0.1118 1.0000第六章第二题clc;clear;close allr=round(100*rand(7,5,10);r1=reshape(r(:,:,1),1,35);a1=mean(r1)r2=reshape(r(:,:,2),1,35);a2=mean(r2)r3=reshape(r(:,:,3),1,35);a3=mean(r3)r4=reshape(r(:,:,4),1,35);a4=mean(r4)r5=reshape(r(:,:,5),1,35);a5=mean(r5)r6=reshape(r(:,:,6),1,35);a6=mean(r6)r7=reshape(r(:,:,7),1,35);a7=mean(r7)r8=reshape(r(:,:,8),1,35);a8=mean(r8)r9=reshape(r(:,:,9),1,35);a9=mean(r9)r10=reshape(r(:,:,10),1,35);a10=mean(r10)A=a1 a2 a3 a4 a5 a6 a7 a8 a9 a10B,A=sort(A)a1 = 54.1714a2 = 48a3 = 52.4000a4 = 44.8286a5 = 53.2286a6 = 49.2571a7 = 50.7429a8 = 46.0571a9 = 46.1714a10 = 50.8286A = 54.1714 48.0000 52.4000 44.8286 53.2286 49.2571 50.7429 46.0571 46.1714 50.8286B = 44.8286 46.0571 46.1714 48.0000 49.2571 50.7429 50.8286 52.4000 53.2286 54.1714A = 4 8 9 2 6 7 10 3 5 1第七章第二题clc;clear;close allx=-1:.01:1;y=-2*x.2+4;y1=-2*x.2+4+sin(2*pi*x);figure(1)plot(x,y,x,y1),grid ontext(-0.3,4,最大值rightarrow)text(-1.0,4,极大值rightarrow)text(-0.6,2.8,极小值rightarrow)text(-0.1,4.8,极大值rightarrow)text(0.5,1.7,极小值rightarrow)第四题function word(y)i=1;while(any(y) A(i).Name,y=strtok(y); A(i).no=i; A(i).length=length(A(i).