MATLAB基础教程 薛山 课后答案2-12章.pdf

2 1double (1) a=87b=190a+ba- ba*b (2)uint8(1) 1 a=87 a = 87 b=190 b = 190 a+b ans = 277 a- b ans = - 103 a*b ans = 16530 2 c=uint8(87) c = 87 d=uint8(190) d = 190 c+d ans = 255 c- d ans = 0 c*d ans = 255 2 (1)sin 60 (2) e3 (3) 3 cos 4 1 sind(60) ans = 0.8660 2 exp(3) ans = 20.0855 3 cos(3*pi/4) ans = - 0.7071 32u3v (1) 4 log uv v (2) 2 2 euv vu (3) 3uv uv 1 u=2; v=3; 4*u*v/log(v) ans = 21.8457 2 (exp(u)+v)2/(v2- u) ans = 15.4189 3 sqrt(u- 3*v)/(u*v) ans = 0 + 0.4410i 4 (1)3 542ii (2)sin 28i 1 (3- 5*i)*(4+2*i) ans = 22.0000 - 14.0000i 2 sin(2- 8*i) ans = 1.3553e+003 +6.2026e+002i 5 (1) 4 4 4 4=20 ans = 0 4 4=20 ans = 1 5 b a=39; b=58; c=3; d=7; ab ans = 0 2 a ab disp(sind(60); disp(exp(3)=); disp(exp(3); disp(cos(3*pi/4)=); disp(cos(3*pi/4); 86 a=39; b=58; c=3; d=7; disp(ab),disp(ab); disp(ac),disp(a|bc); disp(d),disp(d); 3 1. x = 9 3 0 6 3 y = mod(sqrt(length(x+5).*1 2 3 4 5)*5),3) y y =2 2.MATLAB a = 3, 7, 2, 7, 9, 3, 4, 1, 6; b = 7; a(4) = ; vec1 = a=b; vec2 = mod(a,2)=0; c = sum(vec1); vec3 = vec1+vec2; d = vec3.*a; vec4 = find(a 5); e = a(vec4) + 5; vec5 = find(a y=(x)exp(x)- x5; x = fzero(y,8) x = 12.7132 fplot(y,x- 1,x+1); hold on plot(x,y(x),r*); 2 y=(x)x*sin(x); x = 0 3. (1) 2 2 1zxy (2) 2 1zxy 1 z = (x)x(1)2- (x(2)- 1)2; x,fvalue,flag,output=fminsearch(z,0,0) Exiting: Maximum number of function evaluations has been exceeded - increase MaxFunEvals option. Currentfunctionvalue: - 35921226633944080000000000000000000000000000000000000000000000000000000000 0000000000.000000 x = 1.0e+041 * 0.9523- 6.0686 fvalue = - 3.5921e+083 flag = 0 output = iterations: 200 funcCount: 401 algorithm: Nelder- Mead simplex direct search message: 1x233 char 2 z = (x)(x(1)- x(2)+1)2; x,fvalue,flag,output=fminsearch(z,0,0) x = - 0.54250.4575 fvalue = 2.4109e- 011 flag = 1 output = iterations: 40 funcCount: 74 algorithm: Nelder- Mead simplex direct search message: 1x196 char implex direct searchimplex direct search message: 1x233 char z = (x)(x(1)- x(2)+1)2; z = (x)(x(1)- x(2)+1)2; x,fvalue,flag,output=fminsearch(z,0,0) x,fvalue,flag,output=fminsearch(z,0,0) 4. (1) 1 35 1 dxxxx (2) 1010 2 11 sind d 4 xy yx y x 1 f = (x)x+x.3+x.5; q = quad(f,- 1,1) q = 2.2204e- 016 (2) f5 = (x,y)sin(y).*(x+y)./(x.2+4); q = dblquad(f5,1,10,1,10) q = 5.5254 5 1 % find the times and places of the specified letter in the string letter = a;% The specified letter to be searched for string = China;% The specified tring to be searched places = findstr(S,A); % The places of the letter ntimes = length(places);% The times of the letter 2 str = this is the string to be converted; nlength = length(str); for k=1:nlength if (k=1 | isspace(str(k-1) end end disp(str); 32212 double cellA = cell(2,2); cellA(1,1) = the first element of the cell; cellA(1,2) = the second element of the cell; cellA(2,1) = uint8(5); cellA(2,2) = 2,3;3,4; 4 structtest=struct(name,number,scores,) (k=1 | isspace(str(k-1) str(k) = char(double(str(k) - 32); (k=1 | isspace(str(k-1) cellA(1,1) = the first element of the cell; cellA(1,2) = the second element of the cell; cellA(1,2) = the second element of the cell; cellA(2,1) = uint8(5); 6 1.x = - 3, 0, 0, 2, 5, 8y = - 5, - 2,0, 3, 4, 10 MATLAB 1z = ydigits(1) vpa(subs(f,x,pi/6) ans = 1. digits(2) vpa(subs(f,x,pi/6) ans = 1.0 digits(5) vpa(subs(f,x,pi/6) ans = 1.0236 digits(10) vpa(subs(f,x,pi/6) ans = 1.023598776 3x 42 1f xxx 32 458g xxxx 1f xg x 2f xg x 3g x 4gf x f = sym(x4 + x2 + 1); g = sym(x3 + 4*x2 + 5*x + 8); 1 f+g ans = f xxxf xxx 4242 f xxx 42424242 f xxxf xxxf xxx 424242 x4+5*x2+9+x3+5*x 2 f*g ans = (x4+x2+1)*(x3+4*x2+5*x+8) 3 finverse(g) Warning: finverse(x3 + 4*x2 + 5*x + 8) is not unique. In sym.finverse at 43 ans = 1/6*(- 656+108*x+12*(2988- 984*x+81*x2)(1/2)(1/3)+2/3/(- 656+108*x+12*(2988- 984*x+81*x2)(1/2)(1/3)- 4/3 4 syms x compose(g,f,x) ans = (x4+x2+1)3+4*(x4+x2+1)2+5*x4+5*x2+13 4 1 22 325325xxxx 3 222 2322521xxyyxyxxyyxy 1 f = sym(3*x -2*x2 + 5 + 3*x2 -2*x - 5); collect(f) ans = x+x2 2 f = sym(2*x2 -3*x*y + y2 -2*x*y -2*x2 + 5*x*y -2*y + 1); collect(f) ans = y2- 2*y+1 5 17798666 2 8 - 2m +512 3 2322 3a (x- y) - 4b (y- x) xyyxyxxyyxyyxyxxyy23225212322521 (x4+x2+1)3+4*(x4+x2+1)2+5*x4+5*x2+13(x4+x2+1)3+4*(x4+x2+1)2+5*x4+5*x2+13 325325325325325325325325325325325325325325325325325325325325 222222222222222 23225212322521 222222222 23225212322521232252123225212322521xyyxyxxyyxyyxyxxyy232252123225212322521232252123225212322521232252123225212322521 f = sym(3*x -2*x2 + 5 + 3*x2 -2*x - 5); f = sym(3*x -2*x2 + 5 + 3*x2 -2*x - 5); 1 factor(sym(779866) ans = (2)*(149)*(2617) 2 factor(sym(- 2*m8 + 512) ans = - 2*(m- 2)*(m+2)*(m2+4)*(m4+16) 3 factor(sym(3*a2*(x- y)3 -4*b2*(y- x)2) ans = (x- y)2*(3*a2*x- 4*b2- 3*a2*y) 6 1 2 sinf xxx0,2 2 32 21f xxx2,2 1 f = sym(sin(x) + x2); ezplot(f,0,2*pi); 2 f = sym(x3 + 2*x2 + 1); ezplot(f,- 2 2); 7 1 0 tansin lim 1 cos2 x xx x 2 32 2sinyxxxy 3lnyxyxy/fx/fy 2 /fx y 4ln(1)yt dx 27 0 ln(1)yt dx 1 limit(sym(tan(x) -sin(x)/(1- cos(2*x) ans = 0 2 f = sym(sin(x) + x2); f = sym(sin(x) + x2); f = sym(x3 + 2*x2 + 1); tansintansin 1 cos21 cos2 tansin x x x x tansin y = sym(x3 -2*x2 + sin(x); diff(y) ans = 3*x2- 4*x+cos(x) 3 f = x*y*log(x+y); fx = diff(f,x) fx = y*log(x+y)+x*y/(x+y) fy = diff(f,y) fy = x*log(x+y)+x*y/(x+y) f2xy = diff(fx,y) f2xy = log(x+y)+y/(x+y)+x/(x+y)- x*y/(x+y)2 4 syms t y = log(1+t); int(y) ans = log(1+t)*(1+t)- t- 1 int(y,0,27) ans = 56*log(2)+28*log(7)- 27 8 1 1 3 n n n 2 1 2 sin 3 n n n 3sin x0Taylor 1 symsum(sym(3/n)n),1,inf) ans = sum(3/n)n,n = 1 Inf) 2 symsum(sym(2n*sin(pi/(3n),1,inf) ans = 3(1/2) 3 taylor(sym(sin(x) ans = x- 1/6*x3+1/120*x5 9 231 321 xy xy x,y = solve(sym(2*x+3*y=1),sym(3*x+2*y=- 1) x = - 1 y = 1 10 22 xy zxe 1x 2y 3xyZ 1 syms x y z = x*exp(- (x2+y2); syms u v fourier(z,x,u) ans = - 1/2*i*pi(1/2)*u*exp(- y2- 1/4*u2) 2 laplace(z,y,v) ans = 1/2*x*exp(- x2)*pi(1/2)*exp(1/4*v2)*erfc(1/2*v) 3 ztrans(z,x,u) ans = - u*diff(ztrans(exp(- x2- y2),x,u),u) ztrans(z,y,v) ans = x*ztrans(exp(- x2- y2),y,v) 11 22 1 exp 2 f xxy33x33y syms x y z = x*exp(- (x2+y2); z = x*exp(- (x2+y2); exp(- y2- 1/4*u2)exp(- y2- 1/4*u2) laplace(z,y,v) z = 1/(2*pi)*exp(- (x2+y2); ezsurf(x,y,z,- 3,3,- 3,3); 8 1.0,2 /104 x=0:pi/10:2*pi; sinx = sin(x); cosx = cos(x); figure,plot(x,sinx,LineWidth,4) hold on,plot(x,cosx,r:,LineWidth,4) hold on,plot(x(find(cosx=sinx),cosx(find(cosx=sinx),r*,LineWidth,4) 2 1sinyxx010x 2 22 6621zxxyyxy1010x1010y 3 22 164 xy z1616x44y 1 x = 0:pi/10:10*pi; plot(x,sin(x) 2 X,Y = meshgrid(- 10:0.5:10); Z = X.2 + 6*X*Y + Y.2 + 6*X + 2*Y - 1; plot3(X,Y,Z) 3 X,Y = meshgrid(- 16:0.4:16,- 4:0.1:4); Z = X.2/16 -Y.2/4; plot3(X,Y,Z) 3. 1 2100010 310010 1pie 66216621zxxyyxy66216621662166216621 16161616161616161616161616161616161616161616 10101010101010101010 4444y y444444444444 X,Y = meshgrid(- 10:0.5:10); X,Y = meshgrid(- 10:0.5:10); Z = X.2 + 6*X*Y + Y.2 + 6*X + 2*Y - 1; Z = X.2 + 6*X*Y + Y.2 + 6*X + 2*Y - 1; 2 hist(round(rand(100,1)*10) 3 X = round(rand(10,1)*10); stairs(X) 4.1 title(); gtext(sin(x) gtext(cos(x) legend(sin(x),cos(x) 5.2 viewcolormap 9 1 lnfx010x figure,title(),plot(0:0.2:10, log(0:0.2:10) 2 4 22 22 1 xy ab ab figure(Color,y); set(gca,DefaultLineLineWidth,4); a = 4; b = 3; x = linspace(-a,a,100); y1 = sqrt(1-x.2/(a2)*b2); y2 = -sqrt(1-x.2/(a2)*b2); plot(x,y1); hold on; plot(x,y2); 3MATLAB cos 2sin 2 t x t t y t 22t t = -2:0.1:2; x = cos(t/pi); y = 2*sin(t/(2*pi); figure,plot(t,x); hold on; plot(t,y); %if waitforbuttonpress while(1) if waitforbuttonpress=0 get(gcf,CurrentObject); c = ceil(rand) * 5); switch c case 1 2222t t222222222222 set(get(gcf,CurrentObject),Color, r); case 2 set(get(gcf,CurrentObject),Color, g); case 3 set(get(gcf,CurrentObject),Color, b); case 4 set(get(gcf,CurrentObject),Color, k); case 5 set(get(gcf,CurrentObject),Color, y); end end end 10 1MATLABGUI 2GUI 3callbackfunction 4GUIGUI 5GUI 2 yaxbxcabca 11 1.SimulinkCommonly used Blocks 2. 2 1 1223 2 213 123 4 210 8 xxxx x xxx xxx 123 0xxx Simulink 1 x 2 x 3 x 1 x 2 x