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    <blockquote type="cite"
cite="mid:CAMYG4Gm+5mcT5xvgk_z-t9eiQY0spgjm6V3fdWbe5fXoYvUB5w@mail.gmail.com">
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        <div class="gmail_quote">MATNEST is only a storage optimization
          after everything works right. It does
          <div>not have to do with solving.</div>
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    Thanks for the answer. I hoped that I could use block solvers suited
    for MATNEST, which apparently work for a variable-sized block
    matrix. To the extend of my knowledge, MatCreateBAIJ only accepts
    constant block sizes. <br>
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cite="mid:CAMYG4Gm+5mcT5xvgk_z-t9eiQY0spgjm6V3fdWbe5fXoYvUB5w@mail.gmail.com">
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          Something is very wrong there. I advise you to also try
          SuperLU and MUMPS.<br>
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    I will try to compile them on windows, and report the result here.<br>
    <br>
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cite="mid:CAMYG4Gm+5mcT5xvgk_z-t9eiQY0spgjm6V3fdWbe5fXoYvUB5w@mail.gmail.com">
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          <div>Iterative methods depend sensitively on the equation, as
            opposed to direct</div>
          <div>solvers which almost do not care. The first step in
            designing an iterative solver</div>
          <div>that PETSc can implement is to find in the literature
            where one has worked for</div>
          <div>your problem.</div>
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    What I'm trying to solve here, has never been studied before
    (compositional fractured petroleum reservoir simulation+coupled
    phase equilibrium formulation+diffusion mass transfer), therefore I
    can not seek help from the literature.<br>
    <br>
    Best wishes,<br>
    Ali<br>
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