petsc-3.14.6 2021-03-30

PetscIsNanReal

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

Synopsis

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

Input Parameter

- the floating point number

Notes

uses the C99 standard isnan() on systems where it exists. Otherwises uses (a != a), note that some optimizing compiles compile out this form, thus removing the check.

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