VMS Help FORTRAN, Intrinsic Procedures, MAX1  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  MAX1 (number, number, ...)

  A function that returns the greatest of the values specified in the
  argument list.
  +------+---------+----------+------------+-------------+
  | Args | Generic | Specific |  Argument  | Result Type |
  +------+---------+----------+------------+-------------+
  |  n   |  MAX1   | IMAX1    | REAL*4     | INTEGER*2   |
  |      |         | JMAX1    | REAL*4     | INTEGER*4   |
  +------+---------+----------+------------+-------------+
  The function returns an INTEGER*4 value if the /I4 command
  qualifier is in effect; otherwise, it returns an INTEGER*2 value.

  See also the MAX intrinsic function.