Modify the fvMatrix.

yehaixuan · September 22, 2016, 16:47

Hi all,

I am trying to add some off-diagonal value to a fvMatrix instance, say, setting a[i][j] = 2 (which is zero before). And i , j are the row and col, respectively.

So what I am not sure about is how many things I need to play around with? Is it enough to modify only lower() ( or upper() ), lowerAddr() and upperAddr()?

A further question is if I need to frequently insert values to the list or field above. What is the computational efficient way to do that?

Btw, I don't need to worry about the boundaryCoeffs and internalCoeffs.

Thanks in advance.

charles4allme · April 11, 2019, 16:10

Hey,

Did you figure out the answer to your problem.

thang_cegroup · April 13, 2019, 08:51

Do you find the answer ? If yes , Could u explain to me ?
I need to modify the matrix coefficient with cyclic boundary which is not implemented for blockmatrix in foam ext-4.0 . But I do not know how to deal with it .

September 22, 2016, 16:47	Modify the fvMatrix.	#1
yehaixuan New Member Haixuan Ye Join Date: May 2012 Location: Ann Arbor, MI, USA Posts: 4 Rep Power: 14	Hi all, I am trying to add some off-diagonal value to a fvMatrix instance, say, setting a[i][j] = 2 (which is zero before). And i , j are the row and col, respectively. So what I am not sure about is how many things I need to play around with? Is it enough to modify only lower() ( or upper() ), lowerAddr() and upperAddr()? A further question is if I need to frequently insert values to the list or field above. What is the computational efficient way to do that? Btw, I don't need to worry about the boundaryCoeffs and internalCoeffs. Thanks in advance.

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April 11, 2019, 16:10		#2
charles4allme Member Join Date: Feb 2018 Posts: 91 Rep Power: 8	Hey, Did you figure out the answer to your problem.

April 13, 2019, 08:51		#3
thang_cegroup New Member Thang Join Date: Apr 2019 Posts: 5 Rep Power: 7	Do you find the answer ? If yes , Could u explain to me ? I need to modify the matrix coefficient with cyclic boundary which is not implemented for blockmatrix in foam ext-4.0 . But I do not know how to deal with it .