FORTRAN Reference Manual

Intrinsic Functions
FORTRAN Reference Manual—528615-001
8-13
DBLE Function
Considerations
•
The result type of the COSH function is the same as the type of its argument.
The value of COSH (x) is defined as
(EXP (x) - EXP (- x))/2.0
•
Note that for all values of x
COSH (- x) = COSH (x)
and
COSH (x) ≥ 1.0
Example of the COSH Function
y = COSH (x)
DBLE Function
The DBLE function returns a double precision value.
x
is an expression of any numeric type.
Considerations
•
For an argument of double precision type, DBLE (x) returns x.
•
For an argument of integer or real type, DBLE (x) returns a value with as much
precision of the significant part of x as a double precision datum can contain.
•
For an argument of complex type, DBLE (x) returns the real part of x with as much
precision of the significant part of x as a double precision datum can contain.
Example of the DBLE Function
DOUBLE PRECISION tincome
tincome = DBLE (pay) * population
DBLE ( x)