Hi! I am trying to find the mesh coordinate where my solution is maximum. In the following MWE, I am solving the Poisson equation with 0 BC on a disk of radius 3. To find the coordinate where the solution attains its max, I implemented the following lines of code: import numpy as np max_index = np.…

The mesh coordinates and the coordinates of the dofs are not the same, To get the coordinates of the degrees of freedom, you need to use x= W1.tabulate_dof_coordinates() print(x[max_index])

[image] dokken: x= W1.tabulate_dof_coordinates() print(x[max_index]) Thanks. It worked. But can you explain what x= W1.tabulate_dof_coordinates() does?

It tabulates (in other words compute) the coordinates of the degrees of freedom (the entries in u.vector()). Imagine that you have a second order lagrange space on a triangle. Then your degrees of freedom no longer align with the mesh vertices, and therefore you need to compute/tabulate them

How to find the coordinate where a vector function is max?

violetus August 6, 2023, 6:52am 5

Hi, how do I find different maximum values for different subdomains ? I have created a post here How to calculate two max values of vector in two different subdomains?

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How to find the coordinate where a vector function is max?

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