ieee_support_sqrt

Date:

10-12-2011

NAME

IEEE_SUPPORT_SQRT - Determine if the system has the IEEE form of SQRT for real variables

SYNOPSIS

IEEE_SUPPORT_SQRT ([[X=]x])

IMPLEMENTATION

Cray Linux Environment (CLE)

STANDARDS

Fortran

IEEE Standard For Binary Floating-point Arithmetic

DESCRIPTION

The function IEEE_SUPPORT_SQRT() can be used to determine if a system has the IEEE form of SQRT for a particular kind of real or for all reals. The IEEE form of SQRT returns a -0.0 for the square root of -0.0 and has some accuracy requirements.

This function accepts the following argument:

x

Must be of type real. It may be a scalar or an array.

IEEE_SUPPORT_SQRT() is an inquiry function. The name of this intrinsic cannot be passed as an argument.

NOTES

The IEEE intrinsic procedures use the named constants contained in a system module, so you must include the following statement in your program:

USE, INTRINSIC :: IEEE_ARITHMETIC

RETURN VALUES

The result type and type parameter is default logical.

If x is present, the result is true if the system has the IEEE form of SQRT for real variables of the same kind type as x; otherwise, the result is false.

If x is not present, the result is true if the system has the IEEE form of SQRT for all real variables supported on this system; otherwise, the result is false.

EXAMPLES

Example 1:

USE, INTRINSIC :: IEEE_ARITHMETIC
REAL xdef
REAL(8)       x8
LOGICAL x_sqrt_supported, allx_sqrt_supported

x_sqrt_supported = IEEE_SUPPORT_SQRT(xdef)

allx_sqrt_supported = IEEE_SUPPORT_SQRT()