Matlab 用xyz点计算高斯曲率
我将点组织在三个数组中-Matlab 用xyz点计算高斯曲率,matlab,grid,mesh,gaussian,point-clouds,Matlab,Grid,Mesh,Gaussian,Point Clouds,我将点组织在三个数组中-X、Y和Z。我想计算这些点的高斯曲率 我发现这样做(如下),但它似乎需要一个点网格。我知道我可以做[x,y]=meshgrid(x,y)来获得两个输入,但是我如何才能获得z function gc = gcurvature(x,y,z) [xu,xv] = gradient(x); [xuu,xuv] = gradient(xu); [xvu,xvv] = gradient(xv); [yu,yv] = gradient(y);
X
、Y
和Z
。我想计算这些点的高斯曲率
我发现这样做(如下),但它似乎需要一个点网格。我知道我可以做[x,y]=meshgrid(x,y)
来获得两个输入,但是我如何才能获得z
function gc = gcurvature(x,y,z)
[xu,xv] = gradient(x);
[xuu,xuv] = gradient(xu);
[xvu,xvv] = gradient(xv);
[yu,yv] = gradient(y);
[yuu,yuv] = gradient(yu);
[yvu,yvv] = gradient(yv);
[zu,zv] = gradient(z);
[zuu,zuv] = gradient(zu);
[zvu,zvv] = gradient(zv);
for i=1:(size(z,1))
for j=1:(size(z,2))
Xu = [xu(i,j) yu(i,j) zu(i,j)];
Xv = [xv(i,j) yv(i,j) zv(i,j)];
Xuu = [xuu(i,j) yuu(i,j) zuu(i,j)];
Xuv = [xuv(i,j) yuv(i,j) zuv(i,j)];
Xvv = [xvv(i,j) yvv(i,j) zvv(i,j)];
E = dot(Xu,Xu);
F = dot(Xu,Xv);
G = dot(Xv,Xv);
m = cross(Xu,Xv);
n = m/sqrt(sum(m.*m));
L = dot(Xuu,n);
M = dot(Xuv,n);
N = dot(Xvv,n);
gc(i,j) = ((L*N)-M^2)/((E*G)-F^2);
end
end
如果我正确理解您的问题,您应该使用另一个
meshgrid
的“重载”(即语法):
谢谢,但是矩阵必须是二维的,这个网格的输出是三维的。
[x,y,z] = meshgrid(X,Y,Z);