NAG FL Interface
f16dpf (imin_​val)

1 Purpose

f16dpf computes the smallest component of an integer vector, along with the index of that component.

2 Specification

Fortran Interface
Subroutine f16dpf ( n, x, incx, k, i)
Integer, Intent (In) :: n, x(1+(n-1)*ABS(incx)), incx
Integer, Intent (Out) :: k, i
C Header Interface
#include <nag.h>
void  f16dpf_ (const Integer *n, const Integer x[], const Integer *incx, Integer *k, Integer *i)
The routine may be called by the names f16dpf or nagf_blast_imin_val.

3 Description

f16dpf computes the smallest component, i, of an n-element integer vector x, and determines the smallest index, k, such that

4 References

Basic Linear Algebra Subprograms Technical (BLAST) Forum (2001) Basic Linear Algebra Subprograms Technical (BLAST) Forum Standard University of Tennessee, Knoxville, Tennessee

5 Arguments

1: n Integer Input
On entry: n, the number of elements in x.
2: x1+n-1×incx Integer array Input
On entry: the n-element vector x.
If incx>0, xi must be stored in xi-1×incx+1, for i=1,2,,n.
If incx<0, xi must be stored in xn-i×incx+1, for i=1,2,,n.
Intermediate elements of x are not referenced. If n=0, x is not referenced.
3: incx Integer Input
On entry: the increment in the subscripts of x between successive elements of x.
Constraint: incx0.
4: k Integer Output
On exit: k, the index, from the set 1,2,,n , of the smallest component of x. If n0 on input then k is returned as 0.
5: i Integer Output
On exit: i, the smallest component of x. If n0 on input then i is returned as 0.

6 Error Indicators and Warnings

If incx=0, an error message is printed and program execution is terminated.

7 Accuracy

The BLAS standard requires accurate implementations which avoid unnecessary over/underflow (see Section 2.7 of Basic Linear Algebra Subprograms Technical (BLAST) Forum (2001)).

8 Parallelism and Performance

f16dpf is not threaded in any implementation.

9 Further Comments


10 Example

This example computes the smallest component and index of that component for the vector
x= 1,10,11,-2,9 T .  

10.1 Program Text

Program Text (f16dpfe.f90)

10.2 Program Data

Program Data (f16dpfe.d)

10.3 Program Results

Program Results (f16dpfe.r)