petsc-3.3-p7 2013-05-11

PETSC_NULL

standard way of passing in a null or array or pointer

Notes: accepted by many PETSc functions to not set a parameter and instead use some default

This macro does not exist in Fortran; you must use PETSC_NULL_INTEGER, PETSC_NULL_DOUBLE_PRECISION, PETSC_NULL_FUNCTION, PETSC_NULL_OBJECT etc

Developer Note: Why have PETSC_NULL, why not just use NULL? The problem is that NULL is defined in different include files under different versions of Unix. It is tricky to insure the correct include file is always included.

See Also

PETSC_DECIDE, PETSC_DEFAULT, PETSC_IGNORE, PETSC_DETERMINE

Level:beginner
Location:
include/petscsys.h
Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages

Examples

src/sys/random/examples/tutorials/ex1.c.html
src/sys/random/examples/tutorials/ex2.c.html
src/sys/examples/tutorials/ex2.c.html
src/sys/examples/tutorials/ex5.c.html
src/sys/sf/examples/tutorials/ex1.c.html
src/sys/threadcomm/examples/tutorials/ex3.c.html
src/sys/threadcomm/examples/tutorials/ex4.c.html
src/sys/threadcomm/examples/tutorials/ex5.c.html
src/vec/vec/examples/tutorials/ex1.c.html
src/vec/vec/examples/tutorials/ex3.c.html
src/vec/vec/examples/tutorials/ex5.c.html