9.231 SELECTED_INT_KIND — Choose integer kind

Description:

SELECTED_INT_KIND(R) return the kind value of the smallest integer type that can represent all values ranging from -10^R (exclusive) to 10^R (exclusive). If there is no integer kind that accommodates this range, SELECTED_INT_KIND returns -1.

Standard:

Fortran 95 and later

Class:

Transformational function

Syntax:

RESULT = SELECTED_INT_KIND(R)

Arguments:

R	Shall be a scalar and of type INTEGER.

Example:

program large_integers
  integer,parameter :: k5 = selected_int_kind(5)
  integer,parameter :: k15 = selected_int_kind(15)
  integer(kind=k5) :: i5
  integer(kind=k15) :: i15

  print *, huge(i5), huge(i15)

  ! The following inequalities are always true
  print *, huge(i5) >= 10_k5**5-1
  print *, huge(i15) >= 10_k15**15-1
end program large_integers