How to determine that 2.0 == (float) 2 in a front-end.

[Toon Moene]

Tim Josling wrote:

> I have come across situations where for example 2.0 ** N where N > 240 was
> calculated by successive multiplications. This sort of calculation is common
> in net present value calculations, where you use binary search of Newton's
> method to zero in on the correct interest rate given a set of payments. This
> is terribly slow.

Yes, I know this and yes, f/com.c:ffecom_expr_power_integer_ doesn't
have any protection against it.

If it proves a problem in Fortran code, I trim it to some useful value.

The current discussion is whether:

      x**6.0 can be rendered as x**6 (which is y=x*x, z=y*y, z=z*y).

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