matlab程式设计与应用课后实验答案

subplot(3,4,9); stairs(x,y1); subplot(3,4,2); fill(x,y1); 6,

ezsurf('cos(s)*cos(t)','cos(s)*sin(t)','sin(s)',[0,0.5*pi,0,1.5*pi]);

shading interp

实验七： 1,

hf=figure('pointer','cross','position',[50,200,500,500],'menubar','none','color',[1,0,0],'name','窗口示例

','numbertitle','off','resize','off','windowbuttondownFcn','disp(\); 2,

hf=figure('pointer','cross','position',[50,200,500,500],'menubar','none','color',[1,0,0],'name','窗口示例

','numbertitle','off','resize','off','windowbuttondownFcn','disp(\); x=0:pi/100:2*pi; y=x.^2.*exp(2*x); h=line(x,y);

axis([0,2*pi,0,10]) text(1,5,'\\leftarrow y=x^2*exp(2*x) \\pi

\\div','color','b','fontsize',20,'rotation',30)

set(h,'linestyle',':','color','g','linewidth',5); 3,

x=0:pi/100:100; [t,x]=meshgrid(x);

y=10*exp(-0.01*x)*sin(2000*pi*t-0.2*t+pi);

hs=surface(t,x,y);

实验八： 实验8—1 clear all; n=0;

A=rand(1,30000); meanA=mean(A); stdA=std(A,1,2); maxA=max(A); minA=min(A); for x=A if x>0.5 n=n+1;

else continue; end end

p=n/30000;

disp(['均值=' ,num2str(meanA)]); disp(['标准差=',num2str(stdA)]); disp(['最大值

max=',num2str(maxA)]); disp(['最小值

min=',num2str(minA)]);

disp([ '百分比P=',num2str(p)]);

实验九： 2,(1).

x=0:pi/100:2*pi;

y=sqrt(cos(x.^2)+4*sin(2*x).^2+1);

trapz(x,y)

g=inline('sqrt(cos(x.^2)+4*sin(2*x).^2+1)');

i=quadl(g,0,2*pi) j=quad(g,0,2*pi) format short

2,(2).

x=0:0.001:1;

y=log(1+x)./(1+x.^2); trapz(x,y)

g=inline('log(1+x)./(1+x.^2)');

i=quadl(g,0,1) j=quad(g,0,1) format short 3,

a=[6,5,-2,5;9,-1,4,-1;3,4,2,-2;3,-9,0,2];

b=[-4;13;1;11]; x1=a\\b

[l,u]=lu(a); x2=u\\(l\\b)

[q,r]=qr(a); x3=r\\(q\\b) format short 5，

function f=fz(x); f=3*x+sin(x)-exp(x); 6，（1）：

f=inline('(x^3+cos(x)+x*log(x))/exp(x)');

fminbnd(f,0,1)

（2）：function f=fxy(u) x=u(1); y=u(2);

f=2*x.^3+4*x.*y.^2-10*x.*y+y.^2; 实验十：

1, x=sym('6'); y=sym('5');

z=(x+1)/(sqrt(3+x)-sqrt(y))

eval(z)

2, syms x y z=x^4-y^4 factor(z)

factor(sym('5135')) Q35整数分解

3, syms x y

m=sin(x)*cos(y)-cos(x)*sin(y) n=(4*x^2+8*x+3)/(2*x+1) simple(m) %显示过程 simplify(m)

simplify(n) %最优

4, p1=sym('[0,1,0;1,0,0;0,0,1]') p2=sym('[1,0,0;0,1,0;1,0,1]') A=sym('[a,b,c;d,e,f;g,h,i]') B=p1*p2*A

C=inv(B) %逆矩阵

B.*C-C.*B %验证逆矩阵的正确性

triu(B) %上三角阵 tril(B) %下三角阵

diag(B,1) %主对角线 det(B)

5, syms x a t

m=(x*(exp(sin(x))+1)-2*(exp(tan(x))-1))/sin(x)^3

n=(sqrt(pi)-sqrt(acos(x)))/sqrt(x+1)

q=(1-cos(2*x))/x

w=sym('[a^x,t^3;t*cos(x),log(x)]')

e=det(w) limit(m) limit(m,0) limit(m,x,0)

limit(n,x,-1,'right') diff(q) %一阶导数 diff(q,2) %二阶导数 diff(e,x) %对x求偏导

diff(e,t,2) %对t求偏二阶导 diff(diff(e,x),t) %d(de/dx)/dt