Math Vector Library
Programming Reference Manual Fortran
Version 1.0 DD-00002-110

5.2 vrsqrt - Vector reciprocal square root   ⎷--
1/ x

subroutine vrsqrt (n, y, incy, x, incx);
subroutine vrsqrtf(n, y, incy, x, incx);

Given an input vector x  and a result vector y  , this function computes:

y= ⎷1-
    x

5.2.1 Parameters

N - INTEGER

ENTRY: Number of elements of x  and y  .
CONSTRAINT: n ≥1  .

Y - ARRAY OF REAL

EXIT: Result vector y  .
CONSTRAINT: Must contain n× incy  elements.
CONSTRAINT: Must not overlap with array x  .

INCY - INTEGER

ENTRY: Stride for the vector y  .
CONSTRAINT: incy> 0  .

X - ARRAY OF REAL

ENTRY: Input vector x  .
CONSTRAINT: Must contain n× incx  elements.
CONSTRAINT: Must not overlap with array y  .

INCX - INTEGER

ENTRY: Stride for the vector x  .
CONSTRAINT: incx> 0  .