I notice that this article does not use the tiny(), epsilon(), or spacing() intrinsic functions. nearest() is another very useful function for writing portable code, and it has no r1mach() or d1mach() equivalent. All of these fortran intrinsic functions work for any real kind, not just the old single and double precision. Also, just in case it might make a difference, the intrinsics can be used in parameter statements at compile time (and they are likely evaluated at compile time even within expressions), whereas r1mach() and d1mach() are evaluated at run time.
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