:orphan:
# MATSOLVERCHOLMOD
matrix type providing direct solvers (Cholesky) for sequential matrices via the external package CHOLMOD. Use `./configure --download-suitesparse` to install PETSc to use CHOLMOD

Use `-pc_type cholesky` `-pc_factor_mat_solver_type cholmod` to use this direct solver

Consult CHOLMOD documentation for more information about the common parameters
which correspond to the options database keys below.


## Options Database Keys

- ***-mat_cholmod_dbound <0>          -*** Minimum absolute value of diagonal entries of D (None)
- ***-mat_cholmod_grow0 <1.2>         -*** Global growth ratio when factors are modified (None)
- ***-mat_cholmod_grow1 <1.2>         -*** Column growth ratio when factors are modified (None)
- ***-mat_cholmod_grow2 <5>           -*** Affine column growth constant when factors are modified (None)
- ***-mat_cholmod_maxrank <8>         -*** Max rank of update, larger values are faster but use more memory [2,4,8] (None)
- ***-mat_cholmod_factor <AUTO>       -*** (choose one of) `SIMPLICIAL`, `AUTO`, `SUPERNODAL`
- ***-mat_cholmod_supernodal_switch <40> -*** flop/nnz_L threshold for switching to supernodal factorization (None)
- ***-mat_cholmod_final_asis <TRUE>   -*** Leave factors "as is" (None)
- ***-mat_cholmod_final_pack <TRUE>   -*** Pack the columns when finished (use FALSE if the factors will be updated later) (None)
- ***-mat_cholmod_zrelax <0.8>        -*** 3 real supernodal relaxed amalgamation parameters (None)
- ***-mat_cholmod_nrelax <4>          -*** 3 size_t supernodal relaxed amalgamation parameters (None)
- ***-mat_cholmod_prefer_upper <TRUE> -*** Work with upper triangular form (faster when using fill-reducing ordering, slower in natural ordering) (None)
- ***-mat_cholmod_print <3>           -*** Verbosity level (None)
- ***-mat_ordering_type internal      -*** Use the ordering provided by Cholmod





## Note
CHOLMOD is part of SuiteSparse http://faculty.cse.tamu.edu/davis/suitesparse.html


## See Also
 [](ch_matrices), `Mat`, `PCCHOLESKY`, `PCFactorSetMatSolverType()`, `MatSolverType`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/sbaij/seq/cholmod/sbaijcholmod.c.html#MATSOLVERCHOLMOD">src/mat/impls/sbaij/seq/cholmod/sbaijcholmod.c</A>


---
[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/mat/impls/sbaij/seq/cholmod/sbaijcholmod.c)


[Index of all Mat routines](index.md)  
[Table of Contents for all manual pages](/manualpages/index.md)  
[Index of all manual pages](/manualpages/singleindex.md)