Intel® Fortran Compiler 18.0 Developer Guide and Reference
Elemental Intrinsic Function (Generic): Returns the absolute value of the first argument times the sign of the second argument.
result = SIGN (a, b)
a |
(Input) Must be of type integer or real. |
b |
(Input) Must have the same type as a. |
The result type and kind are the same as a. The value of the result is as follows:
| a | if b > zero and -| a | if b < zero.
| a | if b is of type integer and is zero.
If b is of type real and zero and compiler option assume minus0 is not specified, the value of the result is | a |.
If b is of type real and zero and compiler option assume minus0 is specified, the processor can distinguish between positive and negative real zero and the following occurs:
If b is positive real zero, the value of the result is | a |.
If b is negative real zero, the value of the result is -| a |.
The specific named versions of the function require that the arguments have the same kind parameters.
Specific Name |
Argument Type |
Result Type |
|---|---|---|
BSIGN |
INTEGER(1) |
INTEGER(1) |
IISIGN1 |
INTEGER(2) |
INTEGER(2) |
ISIGN 2 |
INTEGER(4) |
INTEGER(4) |
KISIGN |
INTEGER(8) |
INTEGER(8) |
SIGN 3 |
REAL(4) |
REAL(4) |
DSIGN 3,4 |
REAL(8) |
REAL(8) |
QSIGN |
REAL(16) |
REAL(16) |
1 Or HSIGN. 2 Or JISIGN. For compatibility with older versions of Fortran, ISIGN is treated as a generic function. 3 The setting of compiler options specifying real size can affect SIGN and DSIGN . 4 The setting of compiler options specifying double size can affect DSIGN. |
||
SIGN (4.0, -6.0) has the value -4.0.
SIGN (-5.0, 2.0) has the value 5.0.
The following shows another example:
c = SIGN (5.2, -3.1) ! returns -5.2
c = SIGN (-5.2, -3.1) ! returns -5.2
c = SIGN (-5.2, 3.1) ! returns 5.2