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Je veux calculer les courbures moyennes et gaussiennes de certains points dans un nuage de points. J'ai x, y, z, qui sont des coordonnées et sont des tableaux 1d. Je veux utiliser le code ci-dessous, mais dans les paramètres d'entrée X, Y et Z sont des tableaux 2d, je ne sais pas ce que cela signifie, et comment je peux calculer les tableaux 2d qui leur correspondent. Merci beaucoupcalculer la courbure de la surface dans matlab
function [K,H,Pmax,Pmin] = surfature(X,Y,Z),
% SURFATURE - COMPUTE GAUSSIAN AND MEAN CURVATURES OF A SURFACE
% [K,H] = SURFATURE(X,Y,Z), WHERE X,Y,Z ARE 2D ARRAYS OF POINTS ON THE
% SURFACE. K AND H ARE THE GAUSSIAN AND MEAN CURVATURES, RESPECTIVELY.
% SURFATURE RETURNS 2 ADDITIONAL ARGUEMENTS,
% [K,H,Pmax,Pmin] = SURFATURE(...), WHERE Pmax AND Pmin ARE THE MINIMUM
% AND MAXIMUM CURVATURES AT EACH POINT, RESPECTIVELY.
% First Derivatives
[Xu,Xv] = gradient(X);
[Yu,Yv] = gradient(Y);
[Zu,Zv] = gradient(Z);
% Second Derivatives
[Xuu,Xuv] = gradient(Xu);
[Yuu,Yuv] = gradient(Yu);
[Zuu,Zuv] = gradient(Zu);
[Xuv,Xvv] = gradient(Xv);
[Yuv,Yvv] = gradient(Yv);
[Zuv,Zvv] = gradient(Zv);
% Reshape 2D Arrays into Vectors
Xu = Xu(:); Yu = Yu(:); Zu = Zu(:);
Xv = Xv(:); Yv = Yv(:); Zv = Zv(:);
Xuu = Xuu(:); Yuu = Yuu(:); Zuu = Zuu(:);
Xuv = Xuv(:); Yuv = Yuv(:); Zuv = Zuv(:);
Xvv = Xvv(:); Yvv = Yvv(:); Zvv = Zvv(:);
Xu = [Xu Yu Zu];
Xv = [Xv Yv Zv];
Xuu = [Xuu Yuu Zuu];
Xuv = [Xuv Yuv Zuv];
Xvv = [Xvv Yvv Zvv];
% First fundamental Coeffecients of the surface (E,F,G)
E = dot(Xu,Xu,2);
F = dot(Xu,Xv,2);
G = dot(Xv,Xv,2);
m = cross(Xu,Xv,2);
p = sqrt(dot(m,m,2));
n = m./[p p p];
% Second fundamental Coeffecients of the surface (L,M,N)
L = dot(Xuu,n,2);
M = dot(Xuv,n,2);
N = dot(Xvv,n,2);
[s,t] = size(Z);
% Gaussian Curvature
K = (L.*N - M.^2)./(E.*G - F.^2);
K = reshape(K,s,t);
% Mean Curvature
H = (E.*N + G.*L - 2.*F.*M)./(2*(E.*G - F.^2));
H = reshape(H,s,t);
% Principal Curvatures
Pmax = H + sqrt(H.^2 - K);
Pmin = H - sqrt(H.^2 - K);