Re: getting same output as gfortran, long_float

[Dennis Lee Bieber <wlfraed@ix.netcom.com>]

On Fri, 1 May 2015 08:52:43 +0200, "Dmitry A. Kazakov"
<mailbox@dmitry-kazakov.de> declaimed the following:

>On Thu, 30 Apr 2015 20:12:47 -0500, Nasser M. Abbasi wrote:
>
>> I found that gfortran can do 128 bit floating point without
>> the use of the compiler switch -fdefault-real-8. Which will
>> map to similar thing as the above Ada construct:
>> 
>> -------------------
>> PROGRAM foo
>> IMPLICIT NONE
>> REAL(KIND = 16) :: x  !-- kind=16 tells it is double quad
>> x = 12.0D0 * 0.0001D0/(1.0D0 * (1.0D0 - 0.1D0)**4 )
>> PRINT *, x
>> END PROGRAM
>> ------------------
>
>I didn't use FORTRAN for decades, but in good old FORTRAN-IV you declare
>specific lengths using T*n, e.g.
>
>INTEGER*2
>REAL*4
>REAL*8
>
	Even that wasn't FORTRAN-IV as I was taught it... F-IV/F66 had

INTEGER
REAL
DOUBLE PRECISION

where INTEGER and REAL used the same size storage.

	The *x notation showed up in extended F-77 versions, as I recall -- and
VAX systems really confused matters with at least four variants (two
different double precision systems; the "normal" one being a single
precision REAL with an additional 32 bits of mantissa [so one could easily
truncate if passing to a single precision function] {F and D float}, the
other with an extended exponent and reduced precision {G float}, and quad
precision {H float})


	The OP is using Fortran-90/95 notation.
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/