3-d order derivative
2 次查看(过去 30 天)
显示 更早的评论
Dear all,
there is the following problem with the calculation of a 3-d order derivative.
I have two vectors of lambda and refractive index, respectively. I take the 3-d order derivative using a gradient().
dndl=gradient(n)./gradient(lambda);
d2ndl2=gradient(dndl)./gradient(lambda);
d3ndl3=gradient(d2ndl2)./gradient(lambda);
When I use a relatively small number of points (for example 3000) , I get a smooth plot.
In the case of more points (30 000) there is some oscillation in the plot.
What is the reason of such behavior?
Thank you a lot.
2 个评论
Matt J
2022-2-13
What do you mean by "use more points"? If it's a different input array why expect the same results?
回答(3 个)
Catalytic
2022-2-13
If the points are too close together, the difference between neighbours will be so small as to be dominated by floating point errors
另请参阅
类别
在 Help Center 和 File Exchange 中查找有关 Curve Fitting Toolbox 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!