rrspacing(3I)

NAME
     RRSPACING - Returns the reciprocal of the relative spacing of numeric
     model numbers near the argument value

SYNOPSIS
     RRSPACING ([X=]x)

IMPLEMENTATION
     UNICOS, UNICOS/mk, IRIX systems

     CF90, MIPSpro 7 Fortran 90

STANDARDS
     Fortran

DESCRIPTION
     The RRSPACING intrinsic function returns the reciprocal of the
     relative spacing of the numeric real model numbers near the argument
     value.  For more information on the real number model, see the
     MODELS(3I) man page.  It accepts the following argument:

     x         Must be of type real.

     RRSPACING is an elemental function.  The name of this intrinsic cannot
     be passed as an argument.

NOTES
     This routine is implemented on CRAY T90 systems that support IEEE
     arithmetic by calls to scalar-only library routines.

RETURN VALUES
     The result type and type parameter are the same as x.  The result has
     the value (|(x)(b**-e) |) (b**p) where b, e, and p are defined in the
     real number model.

EXAMPLES
     The following code was run on several systems:

          REAL(KIND=4) r4
          REAL(KIND=8) r8
          REAL(KIND=16) r16
          REAL rd
          r4=-3.0_4
          r8=-3.0_8
          r16=-3.0_16
          rd=-3.0
          PRINT *,'RRSPACING r4=',RRSPACING(r4)
          PRINT *,'RRSPACING r8=',RRSPACING(r8)
          PRINT *,'RRSPACING r16=',RRSPACING(r16)
          PRINT *,'RRSPACING rd=',RRSPACING(rd)
          END

     On IRIX systems, the results were as follows:

          RRSPACING r4= 12582912.
          RRSPACING r8= 6755399441055744.
          RRSPACING r16= 1.216944576219100225436835007716096E+32
          RRSPACING rd= 12582912.

     On a UNICOS/mk system, the results were as follows:

          RRSPACING r4= 12582912.
          RRSPACING r8= 6755399441055744.
          RRSPACING rd= 6755399441055744.

     On a CRAY T90 system that supports IEEE floating-point arithmetic, the
     results were as follows:

          RRSPACING r4= 12582912.
          RRSPACING r8= 6755399441055744.
          RRSPACING r16= 7.788445287802241442795744493830144E+33
          RRSPACING rd= 6755399441055744.

SEE ALSO
     MODELS(3I)

     Intrinsic Procedures Reference Manual for the printed version of this
     man page.