This manual relates to an old release of the Library.
The documentation for the current release is also available on this site.
NAG Library Manual, Mark 27.1
Interfaces:  FL   CL   CPP   AD 
NAG FL Interface Introduction
F06 (Blas) Chapter Contents
F06 (Blas) Chapter Introduction
f06bl:  FL   CL   CPP   AD 

NAG FL Interface
f06blf (ddiv)

NAG Library Manual, Mark 27.1
Interfaces:  FL   CL   CPP   AD 
NAG FL Interface Introduction
F06 (Blas) Chapter Contents
F06 (Blas) Chapter Introduction
f06bl:  FL   CL   CPP   AD 

▸▿ Contents

© The Numerical Algorithms Group Ltd. 2020
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1 Purpose

f06blf computes the quotient of two real scalars.

2 Specification

Fortran Interface
Function f06blf ( a, b, fail)
Real (Kind=nag_wp) :: f06blf
Real (Kind=nag_wp), Intent (In) :: a, b
Logical, Intent (Out) :: fail
C Header Interface
#include <nag.h>
double  f06blf_ (const double *a, const double *b, logical *fail)
The routine may be called by the names f06blf or nagf_blas_ddiv.

3 Description

f06blf returns the value q via the function name, where
q={ a/b, if ​a/b​ does not overflow, 0, if ​a=0, flmax×sign(a/b), if ​a≠0​ and ​a/b​ would overflow.  
Here flmax is the large value given by 1/(x02amf), and sign(a/0) is taken as sign⁡a.

4 References

None.

5 Arguments

1: a – Real (Kind=nag_wp) Input
On entry: the value a.
2: b – Real (Kind=nag_wp) Input
On entry: the value b.
3: fail – Logical Output
On exit: .TRUE. if a/b would overflow (in which case |q|=flmax) or a=b=0 (in which case q=0); otherwise .FALSE..

6 Error Indicators and Warnings

None.

7 Accuracy

Not applicable.

8 Parallelism and Performance

f06blf is not threaded in any implementation.

9 Further Comments

None.

10 Example

None.
NAG Library Manual, Mark 27.1
Interfaces:  FL   CL   CPP   AD 
NAG FL Interface Introduction
F06 (Blas) Chapter Contents
F06 (Blas) Chapter Introduction
f06bl:  FL   CL   CPP   AD 
© The Numerical Algorithms Group Ltd. 2020