NAG Library Function Document

nag_dload (f16fbc)

Basic Linear Algebra Subprograms Technical (BLAST) Forum (2001) Basic Linear Algebra Subprograms Technical (BLAST) Forum Standard University of Tennessee, Knoxville, Tennessee http://www.netlib.org/blas/blast-forum/blas-report.pdf

5 Arguments

1: n – IntegerInput: On entry: $n$ , the number of elements in $x$ .
Constraint: $n \geq 0$ .
2: alpha – doubleInput: On entry: the scalar $α$ .
3: x[ $\dim$ ] – doubleOutput: Note: the dimension, dim, of the array x must be at least $\max (1, 1 + (n - 1) |incx|)$ .
On exit: the scalar $α$ is scattered with a stride of incx in x. Intermediate elements of x are unchanged.
4: incx – IntegerInput: On entry: the increment in the subscripts of x between successive elements of $x$ .
Constraint: $incx \neq 0$ .
5: fail – NagError *Input/Output: The NAG error argument (see Section 3.6 in the Essential Introduction).

6 Error Indicators and Warnings

NE_BAD_PARAM: On entry, argument $⟨value⟩$ had an illegal value.
NE_INT: On entry, $incx = ⟨value⟩$ .
Constraint: $incx \neq 0$ .
On entry, $n = ⟨value⟩$ .
Constraint: $n \geq 0$ .

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

Not applicable.

9 Further Comments

None.

10 Example

This example initializes four elements of a real vector,

x

, with increment

2

, with the value

α = 0.3

NAG Library Function Documentnag_dload (f16fbc)

+− Contents

1 Purpose

2 Specification

3 Description

4 References