robin wrote:
>
> >
> > A solution should be to use :
> >
> > integer, parameter :: digits = 10 ! my regular precision
> > integer, parameter :: R1 = selected_real_kind(digits)
> > integer, parameter :: R2 = selected_real-kind(2*digits)
> >
> > for portability, i think we should always use kind.
>
> This won't be portable. On many machines, R1 will be double precison
> and R2 will specify 20 digits, which will exceed the available precision.
>
Hello,
you should say: "on a few machines". For, most of compilers on classical scientific Unix platforms (SGI, Sun, IBM,...) handle what is often named a "quadruple precision" kind (128bit), with typically around 30 digit precision.
Regards,
Pierre
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