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

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