NAG Library Routine Document

F16JRF (BLAS_DAMIN_VAL)

1  Purpose

2  Specification

3  Description

4  References

5  Arguments

1:     $\mathrm{N}$ – INTEGERInput

On entry: $n$, the number of elements in $x$.

2:     $\mathrm{X}\left(1+\left(\mathbf{N}-1\right)\times \left|\mathbf{INCX}\right|\right)$ – REAL (KIND=nag_wp) arrayInput

On entry: the $n$-element vector $x$.

If $\mathbf{INCX}>0$, $x_{\mathit{i}}$ must be stored in $\mathbf{X}\left(\left(\mathit{i}-1\right)\times \mathbf{INCX}+1\right)$, for $\mathit{i}=1,2,\dots ,\mathbf{N}$.

If $\mathbf{INCX}<0$, $x_{\mathit{i}}$ must be stored in $\mathbf{X}\left(\left(\mathbf{N}-\mathit{i}\right)\times \left|\mathbf{INCX}\right|+1\right)$, for $\mathit{i}=1,2,\dots ,\mathbf{N}$.

Intermediate elements of X are not referenced. If $\mathbf{N}=0$, X is not referenced.

3:     $\mathrm{INCX}$ – INTEGERInput

On entry: the increment in the subscripts of X between successive elements of $x$.

Constraint: $\mathbf{INCX}\ne 0$.

4:     $\mathrm{K}$ – INTEGEROutput

On exit: $k$, the index, from the set $\left\{1,2,\dots ,\mathbf{N}\right\}$, of the smallest component of $x$ with respect to absolute value. If $\mathbf{N}\le 0$ on input then K is returned as $0$.

5:     $\mathrm{R}$ – REAL (KIND=nag_wp)Output

On exit: $r$, the smallest component of $x$ with respect to absolute value. If $\mathbf{N}\le 0$ on input then R is returned as $0.0$.

6  Error Indicators and Warnings

7  Accuracy

8  Parallelism and Performance

9  Further Comments

10  Example

10.1  Program Text

Program Text (f16jrfe.f90)

10.2  Program Data

Program Data (f16jrfe.d)

10.3  Program Results

Program Results (f16jrfe.r)