Hi Kelly,
Kelly Jones wrote:
perl -le 'printf("%f %f %f\n", 4294967295, 2147483647*2**32,
2147483647*2**32+4294967295)'
4294967295.000000 9223372032559808512.000000 9223372036854775808.000000
Why? The answer is really 9223372036854775807 (one number lower), and
it's obvious that adding 2 and 5 in the units column should yield a 7
in the sum's unit column.
Roundoff error? Bug? How do I work around it?
I guess it is a problem with floating point arithmetic where no floating
point value can be represented exactly by a computer. Take a look at:
http://docs.sun.com/source/806-3568/ncg_goldberg.html
For what it's worth, if you change %f to %u, it works fine [for me, anyway]:
perl -le 'printf("%u %u %u\n", 4294967295, 2147483647*2**32,
2147483647*2**32+4294967295)'
4294967295 9223372032559808512 9223372036854775807
Ray
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