Math Vector Library
Programming Reference Manual Fortran
Version 1.1 DD-00002-111

15.9 vrecp - Vector reciprocal 1/x

subroutine vrecp (n, z, incz, x, incx, y, incy); 
subroutine vrecpf(n, z, incz, x, incx, y, incy); 
 
subroutine vrecp_64 (n, z, incz, x, incx, y, incy); 
subroutine vrecpf_64(n, z, incz, x, incx, y, incy);

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

y= 1/x

15.9.1 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: incy̸= 0  .
BEHAVIOR: A negative stride will traverse the array in reverse.

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: incx̸= 0  .
BEHAVIOR: A negative stride will traverse the array in reverse.