matlab二维三维画图(3)

plot3(x,y,z,'r') hold on x=t; y=-t-2; z=-t/2;

plot3(x,y,z,'bo')

结果：

50-5-1040200-20-505

（3）画三个面：2x?y?z?0,x?3y?z?1,?x?2y?2z?3 解：x=-6:0.1:6;

y=-6:0.1:6;

[X,Y]=meshgrid(x,y) Z1=2.*X-Y;

plot3(X,Y,Z1,'g') hold on

Z2=-X-3.*Y+1; plot3(X,Y,Z2,'b') hold on

Z3=(X-2.*Y+3)/2; plot3(X,Y,Z3,'r')

结果：

3020100-10-20-30-60-4-2024610-10

x?1y?3z??,平面：3x?4y?z?10=0 （4）直线L：112解：clear

t=-10:0.1:10; x=t; y=t+4; z=2.*t+2;

plot3(x,y,z,'r') hold on x=-6:0.1:6; y=-6:0.1:6;

[X,Y]=meshgrid(x,y) Z=-3.*X+4.*Y+10; plot3(X,Y,Z,'bo') grid

结果：

6050403020100-10-20-30-4010050-5-1020-20

4、画出下列图形 x2y2??z2 (1)椭圆锥面：89 x2y2z2(2)椭球面：???112915

x2y2z2 (3)单叶双曲面：?-?112915

x2y2z2 (4)双叶双曲面：--?112915 x2y2??z (5)椭圆抛物面：129解：（1）x=-5:0.1:5;

y=-5:0.1:5;

[X,Y]=meshgrid(x,y);

Z=sqrt(((X.^2)/8)+(Y.^2)/9); surf(X,Y,Z) hold on

surf(X,Y,-Z) shading flat

结果：

2.521.510.50-0.5-1-1.5-2-2.5550-5-50

（3）x=-6:0.1:6;

y=-6:0.1:6;

[X,Y]=meshgrid(x,y)

Z=sqrt(15.*(1+X.^2/12+Y.^2/9)); surf(X,Y,Z) hold on

surf(X,Y,-Z)

结果：

151050-5-10-151050-5-10-10-50105

（4）x=-3:0.1:3;

y=-3:0.1:3;

[X,Y]=meshgrid(x,y)

Z=sqrt(15.*(1+X.^2/12-Y.^2/9)); surf(X,Y,Z) hold on

surf(X,Y,-Z)

结果：

6420-2-4-650-5-3-2-10123

（5）x=-3:0.1:3;

y=-3:0.1:3;

[X,Y]=meshgrid(x,y) Z=(X.^2)/12+(Y.^2)/9; surf(X,Y,Z)

结果：

1.81.61.41.210.80.60.40.20420-2-4-2024