
I would like to ask what is the law of arrangement of the stiffness matrix of the element? I look forward to your reply, thank you!

If it is convenient, please tell me both of the numbering sequences. Especially the numbering in the code.
thank you very much!

On 28/06/2021 09:30, 979439736--- via SfePy wrote:
If it is convenient, please tell me both of the numbering sequences. Especially the numbering in the code.
See [1]:
Locally (in a connectivity row), the DOFs are stored DOF-by-DOF (u_0 in all
local nodes, u_1 in all local nodes, ...).
Globally (in a state vector), the DOFs are stored node-by-node (u_0, u_1,
..., u_X in node 0, u_0, u_1, ..., u_X in node 1, ...).
r.
[1] https://sfepy.org/doc-devel/src/sfepy/discrete/variables.html?highlight=crea...
thank you very much!
SfePy mailing list -- sfepy@python.org To unsubscribe send an email to sfepy-leave@python.org https://mail.python.org/mailman3/lists/sfepy.python.org/ Member address: cimrman3@ntc.zcu.cz

I'm very sorry that I had a problem with the previous statement. What I want to ask is the relationship between the element stiffness matrix and the degree of freedom of the node. Because I want to calculate the element flexibility: c = u’ * ke * u

On 29/06/2021 04:05, 979439736--- via SfePy wrote:
I'm very sorry that I had a problem with the previous statement. What I want to ask is the relationship between the element stiffness matrix and the degree of freedom of the node. Because I want to calculate the element flexibility: c = u’ * ke * u
By "ke * u" you mean the stress in an element? u' is u transposed, u being the displacements?
r.

On 30/06/2021 03:36, 979439736--- via SfePy wrote:
u refers to displacement. Actually, mine is solving strain energy
OK, to evaluate strain energy, you can use (in the context stress_strain() in examples/linear_elasticity/its2D_2.py [1]):
E = ev('dw_lin_elastic.2.Omega(Asphalt.D, u, u)', mode='eval')
It is also possible to get stress and strain in the quadrature points:
strain_qp = ev('ev_cauchy_strain.2.Omega(u)', mode='qp') etc.
Try providing more details or code that we can run, if you need something else.
r.
[1] https://sfepy.org/doc-devel/examples/linear_elasticity-its2D_2.html

Someone solves my question about How can I learn easy method about Python
participants (4)
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979439736@qq.com
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Carina Daniel
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joshiruhi37@gmail.com
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Robert Cimrman