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

12.4 veinst4 - Vector Einstein function E4(x)

subroutine veinst4 (n, y, incy, x, incx); 
subroutine veinst4f(n, y, incy, x, incx); 
 
subroutine veinst4_64 (n, y, incy, x, incx); 
subroutine veinst4f_64(n, y, incy, x, incx);

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

y= E (x)= -x----log(1-e -x)
    4     ex -1

12.4.1 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.