9.256 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 90 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