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What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
Posted Sep 13, 2006 5:14 UTC (Wed) by zooko (subscriber, #2589)Parent article: What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
Using the 64 bit architecture came in handy when doing some scientific programming for my wife. We needed to deal with information which was somewhere around 48 bits per item. The 64-bit compile (port) of Judy Tree would handily store those items for us. To use the 32-bit version of Judy Tree we would have to store them elsewhere and put pointers to them into the Judy Tree.
Unfortunately, my wife valued portability so much that we did the latter. :-)
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What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
Posted Sep 13, 2006 9:12 UTC (Wed) by nix (subscriber, #2304) [Link]
I'm more impressed that you could remember what those awfully-named accessor macros did for long enough to use them. (Or did you do as I did and rename them to something better?)
What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
Posted Sep 13, 2006 9:25 UTC (Wed) by zooko (subscriber, #2589) [Link]
I just kept the man page in another window nearby.
Renaming them might have been worth it, though.
I was really happy with judy's performance. I look forward to using it again. Somebody should write a Python wrapper...
--Z
What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
Posted Sep 13, 2006 11:11 UTC (Wed) by amk (subscriber, #19) [Link]
Andrew Dalke has written PyJudy.
Py* Dalke?
Posted Sep 13, 2006 12:02 UTC (Wed) by gvy (guest, #11981) [Link]
Hm, the same Dalke who wrapped daylight.com API?
What you should (and shouldn't) expect from 64-bit Linux (Linux.com)
Posted Sep 13, 2006 14:17 UTC (Wed) by nix (subscriber, #2304) [Link]
Oh yes, from functionality, performance, and documentation POVs Judy is amazing. :)
just use double?
Posted Sep 14, 2006 1:39 UTC (Thu) by stevenj (subscriber, #421) [Link]
Um, for 48 bits per item you could just use 64-bit double precision, which is portable (now that everyone uses IEEE 754) and has 52 bits in its significand (i.e it can represent 52-bit integers exactly).
just use double?
Posted Sep 21, 2006 11:44 UTC (Thu) by renox (guest, #23785) [Link]
Integer<->float convertion can be quite expensive, so I'm not sure using double is that interesting.