平面与五角柱相交曲线求解与三维图绘制: 1、构建根据输入参数改变位置和角度的平面函数的MATLAB代码 2、构建求解判断五角柱面n边与平面相交曲线的函数 3、绘制其中5种平面与五角柱面相交的曲线
时间: 2023-11-28 20:50:04 浏览: 130
1、构建平面函数的MATLAB代码:
```matlab
function [x, y, z] = plane_func(a, b, c, d, theta_x, theta_y, theta_z, x_range, y_range)
% a, b, c, d:平面方程系数 ax + by + cz + d = 0
% theta_x, theta_y, theta_z:平面旋转角度
% x_range, y_range:平面在x、y轴上的范围
% 构建平面坐标系
[x, y] = meshgrid(x_range, y_range);
z = (-a*x -b*y -d)/c;
% 平面旋转
R_x = [1 0 0; 0 cosd(theta_x) -sind(theta_x); 0 sind(theta_x) cosd(theta_x)];
R_y = [cosd(theta_y) 0 sind(theta_y); 0 1 0; -sind(theta_y) 0 cosd(theta_y)];
R_z = [cosd(theta_z) -sind(theta_z) 0; sind(theta_z) cosd(theta_z) 0; 0 0 1];
R = R_x * R_y * R_z;
xyz = [x(:) y(:) z(:)]';
xyz = R * xyz;
x = reshape(xyz(1,:), size(x));
y = reshape(xyz(2,:), size(y));
z = reshape(xyz(3,:), size(z));
end
```
2、构建五角柱面与平面相交曲线的函数:
```matlab
function [x, y, z] = pentagonal_prism_intersection(a, r, h, P)
% a:五边形边长
% r:底面圆半径
% h:五角柱高度
% P:平面方程系数 ax + by + cz + d = 0
% 构建底面五边形坐标
theta = 72 * (0:4)';
theta = theta + 36;
theta = deg2rad(theta);
x_bottom = r * cos(theta);
y_bottom = r * sin(theta);
% 构建顶面五边形坐标
x_top = x_bottom;
y_top = y_bottom;
z_top = h;
% 构建五边柱侧面坐标
z = linspace(0, h, 10);
x_side = [x_bottom x_top(:,end:-1:1)];
y_side = [y_bottom y_top(:,end:-1:1)];
[X, Y, Z] = meshgrid(x_side, y_side, z);
% 计算所有顶点到平面的距离
dist = zeros(size(X));
for i = 1:numel(X)
P_xyz = [X(i); Y(i); Z(i)];
dist(i) = abs(dot(P_xyz, P(1:3)) + P(4))/norm(P(1:3));
end
% 找到相交的线段
tol = 1e-6;
idx = find(dist(1:end-1,:) < tol & dist(2:end,:) < tol);
idx = unique([idx; idx+1]);
[x, y, z] = deal([]);
for i = 1:length(idx)
[i1, i2] = ind2sub(size(dist), idx(i));
x = [x, X(i1:i1+1, i2)'];
y = [y, Y(i1:i1+1, i2)'];
z = [z, Z(i1:i1+1, i2)'];
end
end
```
3、绘制5种平面与五角柱面相交的曲线:
```matlab
a = 3; % 五边形边长
r = 1; % 底面圆半径
h = 2; % 五角柱高度
% 构建五角柱面
theta = 72 * (0:4)';
theta = theta + 36;
theta = deg2rad(theta);
x_bottom = r * cos(theta);
y_bottom = r * sin(theta);
[X, Y] = meshgrid(x_bottom, y_bottom);
Z = linspace(0, h, 10);
surf(X, Y, Z, 'FaceColor', 'g', 'EdgeColor', 'none', 'FaceAlpha', 0.5);
hold on;
% 构建平面
[x, y, z] = plane_func(1, -2, 1, -1, 30, 45, 0, -3:0.1:3, -3:0.1:3);
surf(x, y, z, 'FaceColor', 'b', 'EdgeColor', 'none', 'FaceAlpha', 0.5);
% 求解相交曲线
P = [1, -2, 1, -1];
[x, y, z] = pentagonal_prism_intersection(a, r, h, P);
plot3(x, y, z, 'r', 'LineWidth', 2)
% 设置坐标轴
axis equal;
xlabel('X');
ylabel('Y');
zlabel('Z');
view(3);
```
其中,P为平面方程系数,由于该方程是通过手动调节得到的,不同的参数会导致不同的相交曲线,因此需要根据需要修改P的值。其他4种平面与五角柱面相交的曲线的绘制方法与上述类似。
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