How to zero all values on a particular row?

[Ben Tay]

Hi,

I need to insert values into a matrix and then solve this poisson eqn as
part of my cfd code. For efficiency sake, I  simply use

"do j=1,size_y

 do i=1,size_x

  matsetvalue ....

 end do

end do"

to insert values into all the cells

Then for specific cells, I need to enter some other values. In other words,
for specific rows of the matrix, I need to zero the whole row and insert new
values. How can I do that?

I tried to use MatZeroRows but it says it's not for unassembled matrix. But
I need to zero the particular row, insert values, and then finally assembly
it. Is there a command to do this?

Thanks
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