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Alf Peake wrote:
> /* Re my earlier post _Pinching points_ and responses by Chris Colefax
and
> Bill DeWitt:
> I get a non-fatal "Domain error in pow" each pass through the loop
below if
> in pow(A,B) B is not an integer and I use the D2 section. Both
sections
> should be the same and do evaluate the same. Is there a mistake in my
script
> that I'm missing? The docs say pow(float,float).
to which Jerome M. BERGER <jbe### [at] enst fr> replied:
> Yes but if the second number is not an integer, the first one must be
> greater than 0...
> The way I see it:
> * in the first example, PoV only evaluates the right #declare and the
> test ensures that the value is correct;
> * in the second example, PoV evaluates both values (or tries to) and
> then chooses according to the result of the test, which generates an
> error since one of the values is incorrect...
This is precisely the case, and so it would be correct (indeed,
necessary) to use the full #if () #declare ... #else #declare ... #end
syntax if you wanted to use non-integer powers (but I guess some of us
just can't resist a shortcut!).
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