nag_drscl (f06fec) (PDF version)
f06 Chapter Contents
f06 Chapter Introduction
NAG C Library Manual

NAG Library Function Document

nag_drscl (f06fec)

+ Contents

    1  Purpose
    7  Accuracy
    9  Example

1  Purpose

nag_drscl (f06fec) multiplies a real vector by the reciprocal of a scalar.

2  Specification

#include <nag.h>
#include <nagf06.h>
void  nag_drscl (Integer n, double alpha, double x[], Integer incx)

3  Description

nag_drscl (f06fec) performs the operation
x1 α x
where x is an n-element real vector scattered with stride incx and α is a real nonzero scalar.

4  References

None.

5  Arguments

1:     nIntegerInput
On entry: n, the number of elements in x.
2:     alphadoubleInput
On entry: the scalar α.
Constraint: alpha0.0.
3:     x[dim]doubleInput/Output
Note: the dimension, dim, of the array x must be at least max1, 1+n-1 ×incx .
On entry: the n-element vector x. xi must be stored in x[1+i-1×incx], for i=1,2,,n.
Intermediate elements of x are not referenced.
On exit: the updated vector x, stored in the same array elements used to supply the original vector.
4:     incxIntegerInput
On entry: the increment in the subscripts of x between successive elements of x.
Constraint: incx>0.

6  Error Indicators and Warnings

None.

7  Accuracy

Not applicable.

8  Further Comments

None.

9  Example

None.

nag_drscl (f06fec) (PDF version)
f06 Chapter Contents
f06 Chapter Introduction
NAG C Library Manual

© The Numerical Algorithms Group Ltd, Oxford, UK. 2012