DOC《附：》

linewidth'

,2), set(hc(6),'

edgecolor'

,[1,0.8,0],'

linestyle'

,'

:'

) set(hc(10),'

marker'

,'

*'

) 等函数就可以对线宽、线形、颜色等属性进行控制或加各种标记点. CONTOUR Contour plot. CONTOUR(Z) is a contour plot of matrix Z treating the values in Z as heights above a plane. A contour plot are the level curves of Z for some values V. The values V are chosen automatically. CONTOUR(X,Y,Z) X and Y specify the (x,y) coordinates of the surface as for SURF. CONTOUR(Z,N) and CONTOUR(X,Y,Z,N) draw N contour lines, overriding the automatic value. CONTOUR(Z,V) and CONTOUR(X,Y,Z,V) draw LENGTH(V) contour lines at the values specified in vector V. Use CONTOUR(Z,[v v]) or CONTOUR(X,Y,Z,[v v]) to compute a single contour at the level v. [C,H] = CONTOUR(...) returns contour matrix C as described in CONTOURC and a column vector H of handles to LINE or PATCH objects, one handle per line. Both of these can be used as input to CLABEL. The UserData property of each object contains the height value for each contour. The contours are normally colored based on the current colormap and are drawn as PATCH objects. You can override this behavior with the syntax CONTOUR(...,'

LINESPEC'

) to draw the contours as LINE objects with the color and linetype specified. Uses code by R. Pawlowicz to handle parametric surfaces and inline contour labels. Example: [c,h] = contour(peaks(60),10);

clabel(c,h), colorbar set(h (4),'

linewidth'

,2) set(h (6),'

edgecolor'

,[1,0.8,0],'

linestyle'

,'

:'

) set(h (10),'

marker'

,'

*'

) %展开表达式f=(x+1)^5和f=sin(x+y). % 分别求解代数方程ax^2+bx+c和cos(2x)+sin(x)=1. % 对表达式x9-1 进行因式分解. % 对于表达式f=x*(x*(x-6)+12)*t,分别将自变量x和t的同类项合并. % 计算两多项式x^4-5x^3+3x^2-4x+2和x^3+2x^2-5x+3的乘法. a=[1 -5

3 -4 2];

b=[1

2 -5 3];

c=conv(a,b) 【例3-18】使用两种方法求解欠定系统. a=[1

1 1;

1

1 -1] b=[10 6]'

% 使用不同的Y坐标,在一个图形窗口中绘制两组数据曲线. t=0:900;

A=1000;

a=0.005;

b=0.005;

z1=A*exp(-a*t);

z2=sin(b*t);

% 在图形中使用指定的TeX字符. t=0:pi/100:2*pi;

alpha=-0.8;

beta=15;

y=sin(beta*t).*exp(alpha*t);

在图形中添加图例. 生成数据,绘制图形,在图形中添加图例(图5-53). >

>

x=0:pi/10:2*pi;

>

>

y1=sin(x);

>

>

y2=0.6*sin(x);

>

>

y3=0.3*sin(x);

%在图形中加注坐标轴标识和标题. 【例4-9】展开表达式f=(x+1)^5和f=sin(x+y). syms x y f=(x+1)^5;

expand(f) f=sin(x+y);

expand(f) % 【例4-21】分别求解代数方程ax^2+bx+c和cos(2x)+sin(x)=1. syms a b c x s=a*x^2+b*x+c;

solve(s) solve('

cos(2*x)+sin(x)=1'

) % 【例4-7】对表达式x9-1 进行因式分解. syms x f=factor(x^9-1) pretty(f) % 【例4-10】对于表达式f=x*(x*(x-6)+12)*t,分别将自变量x和t的同类项合并. syms x t f=x*(x*(x-6)+12)*t;

collect(f) collect(f,t) a=[1 -5

3 -4 2];

b=[1

2 -5 3];

c=conv(a,b) 【例3-18】使用两种方法求解欠定系统. a=[1

1 1;

1

1 -1] b=[10 6]'

p=a\b q=pinv(a)*b % 【例5-12】使用不同的Y坐标,在一个图形窗口中绘制两组数据曲线. t=0:900;

A=1000;

a=0.005;

b=0.005;

z1=A*exp(-a*t);

z2=sin(b*t);

plotyy(t,z1,t,z2,'

semilogy'

,'

plot'

);

% 【例5-51】在图形中使用指定的TeX字符. t=0:pi/100:2*pi;