<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi,<div><br></div><div> I have a few questions about the block format matrix.</div><div> </div><div> In the function: <a name="MatCreateSeqBAIJ"><h1 style="display: inline !important; "><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; font-weight: normal;">MatCreateSeqBAIJ, the arguments are </span></font></font></h1></a></div><div><br></div><div><span class="Apple-style-span" style="font-family: Times; font-size: 16px; "><table border="0" cellpadding="0" cellspacing="0" style="position: static; z-index: auto; "><tbody><tr><td align="LEFT" valign="TOP"><font class="Apple-style-span" face="Helvetica">bs</font></td><td><font class="Apple-style-span" face="Helvetica">- </font><a href="file:///Users/manav/Documents/codes/numerical_lib/petsc/petsc-2.3.3-p13/docs/manualpages/Sys/size.html#size"><font class="Apple-style-span" face="Helvetica">size</font></a><font class="Apple-style-span" face="Helvetica"> of block</font></td></tr><tr><td width="40"></td><td align="LEFT" valign="TOP"><font class="Apple-style-span" face="Helvetica">m</font></td><td><font class="Apple-style-span" face="Helvetica">- number of rows</font></td></tr><tr><td width="40"></td><td align="LEFT" valign="TOP"><font class="Apple-style-span" face="Helvetica">n</font></td><td><font class="Apple-style-span" face="Helvetica">- number of columns</font></td></tr><tr><td width="40"></td><td align="LEFT" valign="TOP"><font class="Apple-style-span" face="Helvetica">nz</font></td><td><font class="Apple-style-span" face="Helvetica">- number of nonzero blocks per block row (same for all rows)</font></td></tr><tr><td width="40"></td><td align="LEFT" valign="TOP"><font class="Apple-style-span" face="Helvetica">nnz</font></td><td><font class="Apple-style-span" face="Helvetica">- array containing the number of nonzero blocks in the various block rows (possibly different for each block row) or </font><a href="file:///Users/manav/Documents/codes/numerical_lib/petsc/petsc-2.3.3-p13/docs/manualpages/Sys/PETSC_NULL.html#PETSC_NULL"><font class="Apple-style-span" face="Helvetica">PETSC_NULL</font></a></td></tr></tbody></table><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;"><br class="webkit-block-placeholder"></span></font></div><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;">If I specify the nnz vector, then what is the dimension of this vector? Is that equal to the block size? If so, then is it assumed that all blocks have the same number of non-zeros per row? </span></font></div><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;"><br></span></font></div><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;">If my blocks have different non-zero patterns, then should I use an AIJ format instead of a BAIJ format? </span></font></div><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;"><br></span></font></div><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;">Thanks,</span></font></div><div><font class="Apple-style-span" face="Helvetica" size="3"><span class="Apple-style-span" style="font-size: 12px;">Manav</span></font></div></span></div></body></html>