PETSc version 3.17.4
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# PetscOptionsSetValue

Sets an option name-value pair in the options database, overriding whatever is already present.

### Synopsis

    #include "petscsys.h"
    PetscErrorCode PetscOptionsSetValue(PetscOptions options,const char name[],const char value[])

Logically Collective

### Input Parameters

| options | - options database, use NULL for the default global database
| name | - name of option, this SHOULD have the - prepended
| value | - the option value (not used for all options, so can be NULL)

### Note

This function can be called BEFORE PetscInitialize()

The collectivity of this routine is complex; only the MPI processes that call this routine will have the affect of these options. If some processes that create objects call this routine and others do not the code may fail in complicated ways because the same parallel solvers may incorrectly use different options on different ranks.

Developers Note: Uses malloc() directly because PETSc may not be initialized yet.

### See Also

PetscOptionsInsert(), PetscOptionsClearValue()

### Level

intermediate

### Location

src/sys/objects/options.c

### Examples

src/sys/tutorials/ex16.c.html
src/sys/tutorials/ex16f.F90.html
src/vec/vec/tutorials/ex5.c.html
src/vec/vec/tutorials/ex10.c.html
src/vec/vec/tutorials/ex5f.F90.html
src/dm/impls/stag/tutorials/ex4.c.html
src/snes/tutorials/ex30.c.html
src/tao/unconstrained/tutorials/eptorsion1.c.html
src/tao/unconstrained/tutorials/rosenbrock1.c.html
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