numerical gradient with extra-large data size

3 次查看（过去 30 天）

显示更早的评论

Yu Li 2018-1-16

1
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/377500-numerical-gradient-with-extra-large-data-size

编辑： Walter Roberson 2018-1-17

Hi:

I have a 3D coordinate with significantly large size: 1e9*3.

and I have value of parameter at each of these points such as T: 1e9*1.

now I need the gradient of T at each direction, such as dT/dx, dT/dy, dT/dz.

is there anyway to do this?

Thanks!

回答（1 个）

Walter Roberson 2018-1-16

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/377500-numerical-gradient-with-extra-large-data-size#answer_300415

You might be able to take advantage of "tall arrays" https://www.mathworks.com/help/matlab/tall-arrays.html

9 个评论
显示 7更早的评论隐藏 7更早的评论

Walter Roberson 2018-1-17

See https://projecteuclid.org/download/pdf_1/euclid.rmjm/1250127676 for a discussion of algorithms, and http://www.tandfonline.com/doi/pdf/10.1080/02626667409493918 for more information on the one they recommend.

But I wonder what you are headed for?

http://journals.ametsoc.org/doi/abs/10.1175/1520-0493%281994%29122%3C1611%3AUOMIFM%3E2.0.CO%3B2 "Use of Multiquadric Interpolation for Meteorological Objective Analysis "

http://www.worldscientific.com/worldscibooks/10.1142/6437 "Meshfree Approximations in MATLAB"

Yu Li 2018-1-17

编辑：Walter Roberson 2018-1-17

Hi:

thanks for your reply. I will read these papers and see if I could find any solution.

the original data sets are come from a high fedelity CFD code using large eddy simulation (LES), the CFD software only exports the velocity but no velocity gradient. but we need the gradient to do further analysis.

Thanks!

请先登录，再进行评论。

请先登录，再回答此问题。

类别

MATLAB Mathematics Interpolation

在 Help Center 和 File Exchange 中查找有关 Interpolation 的更多信息

Community Treasure Hunt

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

Start Hunting!

Translated by