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Extracting global DOF list

Extracting global DOF list

Extracting global DOF list

(OP)
------------------ Problem Description ------------------
DOF / node
y
|
|    ^
Theta)--X

Nodes on a cantilever

|
|N1---N3---N4---N5---N6---N2
|

----------------------------------------------------------


APPROACH 1
----------

In this example when I read the .full file for stiffness matrix using HBMAT (LIST->FILES->BINARY->MATRIX). The output was in Harwell-Boeing format. Rearranging it in matrix form it is easy to see that the stiffness matrix is corresponding to following DOF.

UX3 UY3 TH3 UX4 UY4 TH4 UX5 UY5 TH5 UX6 UY6 TH6 UX2 UY2 TH2

The above DOF list was inferred and NOT read from any file.

APPROACH 2
----------

While if I substructure the complete structure and define all the DOF as Master and then read the .sub file using HBMAT (LIST->FILES->BINARY->MATRIX). The output was in Harwell-Boeing format with following global DOF for the matrix.

UX2 UY2 TH2 UX3 UY3 TH3 UX4 UY4 TH4 UX5 UY5 TH5 UX6 UY6 TH6
*********** Notice the N2 DOF are in front

This order can also be read using (LIST->OTHER->SUPERELEM DATA) on .SUB with "full content" option


QUESTION
---------
Output of .full file in using HBMAT file is much more efficient as it only register the non-zero entries while HB output of .sub file register all the entries including zeros. Thus I will prefer using .full file for big structures.

I have not been able to find a list of unconstrained global DOF corresponding to global matrices when read from .full file. Any help in this direction will greatly help.

Thank you!

HN



 

RE: Extracting global DOF list

(OP)
I was trying to read and write the HB formatted file through GUI. I realized that in command line form HBMAT file has a mapping parameter, which when set to YES writes a .mapping file which has a list of global DOF corresponding to the global matrix.

HN

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