Interpolation of 3D point data
조회 수: 75 (최근 30일)
이전 댓글 표시
Hello, I have a nx5 matrix where column 3, 4 and 5 are x,y,z 3D points respectively. I was wondering how I would interpolate (smooth) this 3D data. Many thanks
댓글 수: 4
Walter Roberson
2016년 4월 20일
What properties does the curve need to have? Are you looking for a spline fit? A pchip fit?
채택된 답변
John D'Errico
2016년 4월 29일
편집: John D'Errico
2016년 4월 29일
You can use my interparc tool, as found on the file exchange. It is designed to solve exactly this problem, in 2 or more dimensions.
xyz = interparc(1000,x,y,z,'spline');
xyz will be a 1000x3 array, where each row is an interpolated point on the curve.
Of course, you can do the interpolation in other ways. If you want to do the work in MATLAB yourself in much the same way as you tried to do it:
t = [0;cumsum(sqrt(diff(x).^2+diff(y).^2+diff(z).^2))];
t = t/t(end);
ti = linspace(0,1,1000);
xx = spline(t,x,ti);
yy = spline(t,y,ti);
zz = spline(t,z,ti);
The above solution, which uses a cumulative piecewise linear arclength as the parameter for interpolation, deals more properly with points that are not uniformly spaced.
댓글 수: 0
추가 답변 (2개)
Walter Roberson
2016년 4월 20일
It looks to me as if you likely want a scattered interpolant.
shellmcg
2016년 4월 28일
댓글 수: 1
John D'Errico
2016년 4월 28일
편집: John D'Errico
2016년 4월 29일
I'm sorry, but this answer is just a poor way of solving the problem, presuming the points are somehow equally spaced. Use of a spline as was done here can cause some strange artifacts.
참고 항목
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!