X02AMF (PDF version)
X02 Chapter Contents
X02 Chapter Introduction
NAG Library Manual
NAG Library Routine Document
X02AMF
Note:
before using this routine, please read the Users' Note for your implementation to check the interpretation of
bold italicised
terms and other implementation-dependent details.
+
−
Contents
1
Purpose
2
Specification
3
Description
4
References
5
Parameters
6
Error Indicators and Warnings
7
Accuracy
8
Further Comments
9
Example
1 Purpose
X02AMF returns the
safe range
of floating point arithmetic.
2 Specification
FUNCTION X02AMF (
)
REAL (KIND=nag_wp) X02AMF
3 Description
X02AMF is defined to be the smallest positive model number
z
such that for any
x
in the range [
z
,
1
/
z
] the following can be computed without undue loss of accuracy, overflow, underflow or other error:
-
x
1
/
x
-
1
/
x
x
log
x
exp
log
x
y
log
x
/
log
y
for any
y
4 References
None.
5 Parameters
None.
6 Error Indicators and Warnings
None.
7 Accuracy
None.
8 Further Comments
None.
9 Example
See
Section 9
in X02AJF.
X02AMF (PDF version)
X02 Chapter Contents
X02 Chapter Introduction
NAG Library Manual
© The Numerical Algorithms Group Ltd, Oxford, UK. 2012