Tim Nikias v2.0 <tim### [at] gmxde> wrote:
> Hm. So I should better use floor() or ceil()? These should
> clip to the same values for different platforms, right? And
> why doesn't int() do that?

  Hmm, you didn't seem to understand what I meant.

  "1.1^30" can give and probably gives a slightly different result
depending on the FPU used. However, the difference is in the very lowest
digits of the result. It doesn't really matter.
  The exact same thing happens with "1.1^30.1". The result is not inherently
wrong, it just isn't exact to the last digit because of the inaccuracy of
floating point numbers.

  For instance, even though mathematically "x^3*x^4" equals to "x^7",
a typical FPU will give you a slightly different result for them for
almost any value of x.
  But this isn't an important error because the difference happens
in the 15th or even higher most important digit.

  Different FPUs can use different algorithms for calculating pow and
thus give a slightly different result.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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