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NAG Toolbox

NAG Toolbox: nag_machine_precision (x02aj)

Purpose

nag_machine_precision (x02aj) returns εε, the value machine precision.

Syntax

[result] = x02aj
[result] = nag_machine_precision

Description

nag_machine_precision (x02aj) returns machine precision, computed as ε = (1/2) × b1p ε = 12 × b1-p , where bb is the arithmetic base (see nag_machine_model_base (x02bh)) and pp is the number of significant base-bb digits (see nag_machine_model_digits (x02bj)).
It is important to note that the definition of εε here differs from that in ISO (1997).

References

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

Parameters

Compulsory Input Parameters

None.

Optional Input Parameters

None.

Input Parameters Omitted from the MATLAB Interface

None.

Output Parameters

1:     result – double scalar
The result of the function.

Error Indicators and Warnings

None.

Accuracy

None.

Further Comments

None.

Example

function nag_machine_precision_example
[result] = nag_machine_precision
 

result =

   1.1102e-16


function x02aj_example
[result] = x02aj
 

result =

   1.1102e-16



PDF version (NAG web site, 64-bit version, 64-bit version)
Chapter Contents
Chapter Introduction
NAG Toolbox

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