f06fd multiplies a real vector by a scalar, preserving the input vector.

Syntax

C#
public static void f06fd( int n, double alpha, double[] x, int incx, double[] y, int incy, out int ifail )

Visual Basic
Public Shared Sub f06fd ( _ n As Integer, _ alpha As Double, _ x As Double(), _ incx As Integer, _ y As Double(), _ incy As Integer, _ <OutAttribute> ByRef ifail As Integer _ )

Visual C++
public: static void f06fd( int n, double alpha, array<double>^ x, int incx, array<double>^ y, int incy, [OutAttribute] int% ifail )

F#
static member f06fd : n : int * alpha : float * x : float[] * incx : int * y : float[] * incy : int * ifail : int byref -> unit

n: Type: System..::..Int32
On entry: $n$ , the number of elements in $x$ and $y$ .

x: Type: array<System..::..Double>[]()[][]
An array of size [dim1]
Note: the dimension of the array x must be at least $\max (1, 1 + (n - 1) \times |incx|)$ .
On entry: the $n$ -element vector $x$ .
If $incx > 0$ , $x_{i}$ must be stored in $x [1 + (i - 1) \times incx]$ , for $i = 1, 2, \dots, n$ .

If $incx < 0$ , $x_{i}$ must be stored in $x [1 - (n - i) \times incx]$ , for $i = 1, 2, \dots, n$ .

Intermediate elements of x are not referenced.

incx: Type: System..::..Int32
On entry: the increment in the subscripts of x between successive elements of $x$ .

y: Type: array<System..::..Double>[]()[][]
An array of size [dim1]
Note: the dimension of the array y must be at least $\max (1, 1 + (n - 1) \times |incy|)$ .
On exit: the vector $y$ .
If $incy > 0$ , $y_{i}$ will be stored in $y [1 + (i - 1) \times incy]$ , for $i = 1, 2, \dots, n$ .

If $incy < 0$ , $y_{i}$ will be stored in $y [1 - (n - i) \times incy]$ , for $i = 1, 2, \dots, n$ .

Intermediate elements of y are unchanged.

incy: Type: System..::..Int32
On entry: the increment in the subscripts of y between successive elements of $y$ .

ifail: Type: System..::..Int32%
On exit: $ifail = 0$ unless the method detects an error (see [Error Indicators and Warnings]).

Description

f06fd performs the operation

y \leftarrow α x

where

x

and

y

are

n

-element real vectors scattered with stride incx and incy respectively, and

α

is a real scalar.

None.

Not applicable.

None.

None.