naginterfaces.library.machine.precision

naginterfaces.library.machine.precision()

precision returns $ϵ$, the value machine precision.

For full information please refer to the NAG Library document for x02aj

https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/x02/x02ajf.html

Returns

epsfloat

$ϵ$, the value machine precision.

Notes

precision returns machine precision, computed as $ϵ=\frac{1}{2}\times b^{1-p}$, where $b$ is the arithmetic base (see model_base()) and $p$ is the number of significant base-$b$ digits (see model_digits()).

It is important to note that the definition of $ϵ$ here differs from that in ISO Fortran 95 (1997).

References

ISO Fortran 95, 1997, ISO Fortran 95 programming language, (ISO/IEC 1539–1:1997)