petsc-3.14.6 2021-03-30
PetscRealIntMultTruncate
Computes the product of a positive PetscReal and a positive PetscInt and truncates the value to slightly less than the maximal possible value
Synopsis
PETSC_STATIC_INLINE PetscInt PetscRealIntMultTruncate(PetscReal a,PetscInt b)
Not Collective
Input Parameter
Returns
the result as a PetscInt value
Use PetscInt64Mult() to compute the product of two PetscInt as a PetscInt64
Use PetscIntMultTruncate() to compute the product of two positive PetscInt and truncate to fit a PetscInt
Use PetscIntMultError() to compute the product of two PetscInt if you wish to generate an error if the result will not fit in a PetscInt
Developers Note
We currently assume that PetscInt addition can never overflow, this is obviously wrong but requires many more checks.
This is used where we compute approximate sizes for workspace and need to insure the workspace is index-able.
Not available from Fortran
See Also
PetscBLASInt, PetscMPIInt, PetscInt, PetscBLASIntCast(), PetscInt64Mult(), PetscIntMultError(), PetscIntSumError()
Level
advanced
Location
include/petscsys.h
Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages