FORTRAN Reference Manual

Intrinsic Functions
FORTRAN Reference Manual—528615-001
8-27
SIGN Function
Considerations
•
For an argument of real type, REAL (x) returns x.
•
For an argument of integer or double precision type, REAL (x) has as much
precision of the significant part of x as a real datum can contain.
•
For an argument of complex type, REAL (x) returns the value of the real part of x.
That is,
REAL(CMPLX(x, y))
returns X.
•
For an integer argument, FLOAT (x) returns the same value as REAL (x).
Example of the REAL Function
total = FLOAT (number) * 2.50
SIGN Function
The SIGN function returns a value after transferring a sign.
The table below shows the argument and function type for the SIGN generic function
and its associated specific functions.
Considerations
•
The result of the SIGN function is of the same type as the arguments. Both
arguments must be of the same type.
•
The value of SIGN (x, y) is defined as:
|x| if y ≥ 0
-|x| if y < 0
Syntax Argument Type Function Type
SIGN (x, y)
SIGN (x, y)Real Real
ISIGN (x, y) Integer Integer
ISIGN4 (x, y) Integer*4 Integer*4
ISIGN8 (x, y) Integer*8 Integer*8
DSIGN (x, y) Double Precision Double Precision
x and y are arithmetic expressions.