PETSc version 3.15.5
PCPreSolve
Optional pre-solve phase, intended for any preconditioner-specific actions that must be performed before the iterative solve itself. 
Synopsis
#include "petscksp.h" 
PetscErrorCode  PCPreSolve(PC pc,KSP ksp)
Collective on PC
Input Parameters
|  | pc | - the preconditioner context | 
|  | ksp | - the Krylov subspace context | 
Sample of Usage
    PCPreSolve(pc,ksp);
    KSPSolve(ksp,b,x);
    PCPostSolve(pc,ksp);
Notes
The pre-solve phase is distinct from the PCSetUp() phase.
KSPSolve() calls this directly, so is rarely called by the user.
See Also
 PCPostSolve()
Level
developer
Location
src/ksp/pc/interface/precon.c
Implementations
PCPreSolve_BDDC in src/ksp/pc/impls/bddc/bddc.c
PCPreSolve_Deflation in src/ksp/pc/impls/deflation/deflation.c
PCPreSolve_Eisenstat in src/ksp/pc/impls/eisens/eisen.c
PCPreSolve_HPDDM in src/ksp/pc/impls/hpddm/hpddm.cxx
PCPreSolve_Shell in src/ksp/pc/impls/shell/shellpc.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages