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I have a large dense matrix (size ranging from 5e4 to 1e5) that arises as a result of doing MatComputeOperator() on a MatShell. When the total number of nonzeros exceeds the 32 bit integer value, I get an error (MPI buffer size too big) when
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<div dir="ltr"><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div style="color:rgb(34,34,34)">I have a large dense matrix (size ranging from 5e4 to 1e5) that arises as a result of doing MatComputeOperator() on a MatShell. When the total number of nonzeros exceeds the 32 bit integer value, I get an error (MPI buffer size too big) when trying to do MatView() on this to save to binary. Is there a way I can save this matrix to load again for later use? </div><div style="color:rgb(34,34,34)"><br></div><div style="color:rgb(34,34,34)">The other thing I tried was to save each column as a separate dataset in an hdf5 file. Then, I tried to load this in python, combine them to an np array, and then create/save a dense matrix with petsc4py. I was able to create the dense Mat, but the MatView() once again resulted in an error (out of memory). </div><div style="color:rgb(34,34,34)"><br></div><div style="color:rgb(34,34,34)">Thanks,</div><div style="color:rgb(34,34,34)">Sreeram</div></div></div></div>