About portable programming in fortran

yuanliu1_at_gmail.com
Date: 03/29/05 

Date: 28 Mar 2005 16:05:13 -0800

I have a fortran code, I want it to work both under single precision
and double precision mode. I made it partly work.
first I define the kind parameter,
integer, parameter :: myprec = selected_real_kind(*) //* can be 6 for
single precision and 15 for double precision.

then everything is declared in this way.
real (myprec) a, b, c

if I want my code to work under double precision, I just set * to 15,
and so on.

but still, this is not perfect. Since for double precision variables, I
have dabs, dsqrt, zsqrt, zexp, dexp. For single precision, I have abs,
sqrt, csqrt, exp...
how to make the intrinsic function portable?? I suppose one way is to
conditionally compile. Am I right?

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