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Unable to find requested PC type ml

0 votes

Hi Everyone
My code runs well on my laptop. But when it runs on another computer, it appears the error
information:

[0]PETSC ERROR: --------------------- Error Message ------------------------------------  
[0]PETSC ERROR: Unknown type. Check for miss-spelling or missing external package   needed for type:
see http://www.mcs.anl.gov/petsc/documentation/installation.html#external!
[0]PETSC ERROR: Unable to find requested PC type ml!

Have you encountered this matter before? Any suggestions are appreciated! Thanks!

asked Aug 20, 2015 by Guodong Zhang FEniCS Novice (420 points)

1 Answer

0 votes

You need to build PETSc with ML. You can do that by configure PETSc with the --download-ml flag.

answered Aug 21, 2015 by johannr FEniCS Expert (17,350 points)

Hi johannr
I can not follow your suggestion. What do you mean " --download-ml flag"? Thank you!

commented Aug 21, 2015 by Guodong Zhang FEniCS Novice (420 points)

This is problem with your PETSc installation. PETSc can be configured with many different backends, including ML. On your laptop, PETSc includes ML, on the other computer, it does not. You need to recompile PETSc to include ML.

commented Aug 24, 2015 by chris_richardson FEniCS Expert (31,740 points)
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