HP Fortran Programmer's Reference (September 2007)

Intrinsic procedures
Intrinsic procedure specifications
Chapter 11608
Class
Inquiry function.
Argument
X must be of type integer or real. It may be scalar or array valued.
Result type,
type parameters,
and shape
Default integer scalar.
Result value
The result has the value r if X is of type integer and the value b if X is of type real, where r and
b are as defined in “The Real Number System Model” on page 509.
RAN(ISEED)
Description
Multiplicative congruent random number generator.
Class
Elemental nonstandard function.
Argument
ISEED must be an INTEGER(4) variable or array element. RAN stores a number in ISEED to be
used by the next call to RAN.
ISEED should initially be set to an odd number, preferably very large; see the following
example.
Result type/
type parameters
REAL(4) type.