# How to find the curvature of a surface plot?

6 ビュー (過去 30 日間)
aneps 2022 年 6 月 24 日
コメント済み: Image Analyst 2022 年 6 月 25 日
I made a surface plot that look like the screenshot below. I want to evaluate the curvature of the top region. The view showed here is a tilted one. If I put in view(0,90), it will look like the second picture attached.. That is the surface where I want to evaluate the curvature. The curve it too small as it is visible... But I want a way to quantify this curve. Is there any way like, put a line diagonally through the surface on view(0,90) and evaluate the curve?
surf(X,Y, Data)
colormap jet;
colorbar
view(0,90)

サインインしてコメントする。

### 採用された回答

Image Analyst 2022 年 6 月 24 日
Youi have to define where the "top part" is, particularly if the whole thing is curved, just to a greater or lesser degree. Is it rotationally symmetric? How about if you just thresholded at some level, like 95% of the max value and took a profile through that and then fit it to a quadratic function? Or if you wanted the sharpenss/curvature of the "edge" you can fit a cross section to a sigmoid function like the rate equation (demo attached).
##### 2 件のコメント表示非表示 1 件の古いコメント
Image Analyst 2022 年 6 月 25 日
I'm not sure you need to fit to a sigmoid shape anyway. Why can't you just take a profile after the surface has bent over and started to flatten out?
And you keep forgetting to attach your data, probably because you never read the posting guidelines :

サインインしてコメントする。

R2019b

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by