Re: Is it time to legitimise REAL*8 etc?

Richard Maine wrote:
Paul van Delst <Paul.vanDelst@xxxxxxxx> wrote:

Could someone explain to me the cumbersomeness of
SELECTED_REAL(INT)_KIND() ??
I agree the syntax is a bit wordy,

Yes, that's one thing - one that I think is more important than you make
it out to be. Another is that it just doesn't match the way most people
want/need to specify things. Decimal digits of precision might seem fine
in theory, but that just isn't a good match the reality of programming.
When what you want to do is select between the 32-, 84- and 128-bit
options for real, it is cumbersome to translate that into numbers of
decimal digits.

O.k., I understand what people take issue with. The interface to people's perceptions is ass-about, but you grapple with the strangeness up front and only once, right? I think the first piece of f90 code I wrote (back in '95) was my Type_Kinds.f90 module that contained definitions for these things (True, I have a test program that output my type kinds results). I've hardly thought about it since then... I just use it. If I want single precision (==real*4) I do
REAL(Single) :: x
or
REAL(sp) :: x
and if I want double (==real*8) I do
REAL(Double) :: x
or
REAL(dp) :: x

(similarly for ints)

It has worked on all platforms I've had access to so far: Sun Solaris, SGI-IRIX, IBM-AIX, HP-UX, PC(linux using pgi, intel, lahey, gfortran, g95), and Macs (intel,gfortran,g95). I definitely do not attribute that portability to my skill as a programmer but to the construct itself.

I mean, if you want to measure the length of various things, you don't construct a brand new measuring stick every time - you get a good one up front and reuse it until you wear it out.

cheers,

paulv

.

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