this seems to lost (complex norm, abs)

[Theodore Papadopoulo]

lfarkas@mindmaker.hu said:
> it contains 2 abs, 2 addition, 2 division, 3 multilication and 1 sqrt
> may be a few cosine and tan help a bit more:-) while the trivial
> "grammar school implementation": sqrt(norm(__z)) 
> contains 1 addition, 2 multilication, 1 sqrt
> so why we use it? may be in case of __z == 0 it's faster a bit, so an

This is done to avoid overflow. Take eg, x = sqrt(DOUBLE_MAX)+epsilon 
and y=0, your formula will overflow (yelding +Infinity) while the used formula 
will give the proper result.


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Theodore Papadopoulo
Email: Theodore.Papadopoulo@sophia.inria.fr Tel: (33) 04 92 38 76 01
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