PetscIsNanReal

Returns whether the PetscReal input is a Not-a-Number (NaN) value.

Synopsis

#if defined(PETSC_USE_REAL___FLOAT128)
PetscBool PetscIsNanReal(PetscReal a)

Input Parameter

• a - the floating point number

Developer Notes

Uses the C99 standard isnan() on systems where it exists.

Otherwise uses (a != a), note that some optimizing compilers compile out this form, thus removing the check.

See Also

PetscIsNormalReal(), PetscIsInfReal()

Level

beginner

Location

src/sys/utils/mathinf.c

---

Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages