Importing variables non-deterministic?

[wxjmfauth at gmail.com]

Le mardi 20 août 2013 09:55:44 UTC+2, Antoon Pardon a écrit :
> Op 20-08-13 09:31, wxjmfauth at gmail.com schreef:
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> > Le mardi 20 août 2013 08:55:18 UTC+2, Antoon Pardon a écrit :
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> >>> If you consider the implementation of sin and cos functions, they usually 
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> >>> reduce the argument modulo π to something in the first quadrant, and then 
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> >>> use symmetry to adjust the value. So changing the value of pi could, in 
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> >>> principle, change the implementation of sin, cos and tan.
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> >> Yes there is this aspect, which is a fair point.
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> >> -- 
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> >> Antoon Pardon
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> > Not really, see my previous post. This is only a geometric
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> > interpretation, useless for calculation.
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> No it is not. Steven is correct that if for example you
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> want the value of sin(10), that in a typical implementation
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> this will be reduced to calculating -sin(10 - 3π).
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> This for two reasons. It is faster to first reduce the argument
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> within the first kwadrant, do the series expansion and then
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> correct for sign than to expand the series with the original
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> argument and it is more acurate because first reducing asures
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> that all terms will stay relatively small while using the
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> original arguments can intrduce some large terms that will
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> have to cancel each other but that will reduce acuracy.
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> -- 
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> Antoon Pardon

Ok. Fine. I was aware of the serie expansion, not
about the reduction.

jmf