PETSc version 3.15.5
MatMFFDCheckPositivity
Checks that all entries in U + h*a are positive or zero, decreases h until this is satisfied. 
Synopsis
#include "petscmat.h"   
PetscErrorCode  MatMFFDCheckPositivity(void *dummy,Vec U,Vec a,PetscScalar *h)
Logically Collective on Vec
Input Parameters
|  | U | - base vector that is added to | 
|  | a | - vector that is added | 
|  | h | - scaling factor on a | 
|  | dummy | - context variable (unused) | 
Options Database Keys
|  | -mat_mffd_check_positivity | 
Notes
This is rarely used directly, rather it is passed as an argument to
MatMFFDSetCheckh()
See Also
  MatMFFDSetCheckh()
Level
advanced
Location
src/mat/impls/mffd/mffd.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages