<div dir="ltr">PETSc solvers will cache any setup computations, like a matrix factorization, and will reuse them on subsequent solves. <div><br></div><div>If you call KSPSetOperators, PETSc will assume its cache is invalid and redo any required setup on subsequent solves.</div><div><div><br></div><div>Mark</div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Apr 9, 2019 at 4:08 AM ztdepyahoo via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">

    

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        <span>Dear group:
        </span></div><div><span>      I need to solve a Laplacian problem Ax=b every time step where A is a constant . I want to store the inverse of A at the first time step. </span></div><div><span>how to do with Petsc</span></div><div><span> Regards</span></div>
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                                <div style="font-size:16px;font-weight:bold;width:100%;white-space:nowrap;overflow:hidden;text-overflow:ellipsis">ztdepyahoo</div>
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                                    <div style="width:100%;word-break:break-all;font-size:14px">ztdepyahoo@gmail.com</div>
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