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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">I want to solve Stokes equation using user defined schur complement preconditioner. So I'm reading and testing snes/examples/tutorial/ex55.c, and ex70.c. In these examples, there
are comments about the usage, for example:
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<div><span style="color: rgb(215, 57, 30); font-family: Menlo; font-size: 11px;">mpiexec -n 2 ./stokes -nx 32 -ny 48 -fieldsplit_1_user_pc. </span>
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<div><span style="font-size: 10pt;">However the option </span><span style="color: rgb(215, 57, 30); font-family: Menlo; font-size: 11px;">-fieldsplit_1_user_pc</span><span style="font-size: 10pt;"> is not recognized by the executable. The output of the above
command is:</span></div>
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residual u = 2.6315e-05</p>
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residual p = 0.000229872</p>
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residual [u,p] = 0.000231373</p>
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discretization error u = 0.00633503</p>
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discretization error p = 0.121534</p>
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discretization error [u,p] = 0.121699</p>
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WARNING! There are options you set that were not used!</p>
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WARNING! could be spelling mistake, etc!</p>
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Option left: name:-fieldsplit_1_user_pc (no value)</p>
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<p style="margin-right: 0px; margin-left: 0px;">I'm wondering what's going on. Is that because I need some specific options during my configuring of the package? By the way, the version of PETSc I'm using is 3.4.4. </p>
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<p style="margin-right: 0px; margin-left: 0px;">Best,</p>
<p style="margin-right: 0px; margin-left: 0px;">Hui</p>
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