Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference

ID 767251
Date 7/13/2023
Public

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Document Table of Contents

FP_CLASS

Elemental Intrinsic Function (Generic): Returns the class of an IEEE* real (binary32, binary64, and binary128) argument. This function cannot be passed as an actual argument.

result = FP_CLASS (x)

x

(Input) Must be of type real.

Results

The result type is INTEGER(4). The return value is one of the following:

Class of Argument

Return Value

Signaling NaN

FOR_K_FP_SNAN

Quiet NaN

FOR_K_FP_QNAN

Positive Infinity

FOR_K_FP_POS_INF

Negative Infinity

FOR_K_FP_NEG_INF

Positive Normalized Number

FOR_K_FP_POS_NORM

Negative Normalized Number

FOR_K_FP_NEG_NORM

Positive Subnormal Number

FOR_K_FP_POS_DENORM

Negative Subnormal Number

FOR_K_FP_NEG_DENORM

Positive Zero

FOR_K_FP_POS_ZERO

Negative Zero

FOR_K_FP_NEG_ZERO

The preceding return values are defined in file for_fpclass.for.

Example

FP_CLASS (4.0_8) has the value 4 (FOR_K_FP_POS_NORM).