### 8.230 `SPACING` — Smallest distance between two numbers of a given type

Description:
  Determines the distance between the argument X and the nearest adjacent number of the same type.
Standard:
  Fortran 95 and later
Class:
  Elemental function
Syntax:
  `RESULT = SPACING(X)`
Arguments:

  X | Shall be of type `REAL`.

Return value:
  The result is of the same type as the input argument X.
Example:

                PROGRAM test_spacing
                  INTEGER, PARAMETER :: SGL = SELECTED_REAL_KIND(p=6, r=37)
                  INTEGER, PARAMETER :: DBL = SELECTED_REAL_KIND(p=13, r=200)

                  WRITE(*,*) spacing(1.0_SGL)      ! "1.1920929E-07"          on i686
                  WRITE(*,*) spacing(1.0_DBL)      ! "2.220446049250313E-016" on i686
                END PROGRAM

See also:
  RRSPACING