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Glenn Maynard wrote:
On Wed, Jun 15, 2005 at 02:54:23PM -0400, Aaron Brown wrote:

Glenn Maynard wrote:

However, all of this goes away if you avoid floating-point

And use 64-bit ints instead?  (Or bignums?)

Yep.  Integers are much more easily predictable than floating-point: no
control word to enable unexpected exceptions, change the rounding
order or precision, no loss of precision due to unexpectedly large
values, results are predictable to the bit--they're much better suited
to measuring fine timings than floating point.

(Of course, not all systems have 64-bit ints, but not all systems
have doubles, either.  Since this is inherently x86-specific, nonportable
code, that's not much of an issue.  For portable code, I usually use
one 32-bit int for seconds, and one for micro- or nanoseconds.)

Actually all machines can have all these data types, it's just a simple matter of software :-)

For me, I really need to use doubles for two reasons. 1) it is the only practical datatype understood by Lua and 2) it is easier for content authors (non-programmers) to understand 1.5 seconds than 1500000 microseconds.

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