tag:blogger.com,1999:blog-19077731.post559111548043464533..comments2020-04-30T02:01:31.054-05:00Comments on Computer cladistics / ¡Cladística a la lata!: Algorithms for phylogenetics 0a: BitfieldsSalvahttp://www.blogger.com/profile/01062764779798191688noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-19077731.post-80909849090326246542009-04-25T14:20:00.000-05:002009-04-25T14:20:00.000-05:00Thanks Mike!
A similar approach (not exactly to t...Thanks Mike!<br /><br />A similar approach (not exactly to taxonomies, it is for tree shapes) was used by Farris [Syst. Zool. 22: 50, 1973] to compare trees.<br /><br />The problem with this, is that as the tree grows, the number of redundant fields increase (if you have a bit for each mammal family, each other branch of the tree-of-life have this bits always in 0).<br /><br />A guess that if the meaning of the low-order bits depends on the high-order bits, a bunch of memory can be saved, but surely it require a more complex comparison mechanism.<br /><br />For example (((a b) (c d))((e f)(g h))) can be stored as<br />a 110 000<br />b 110 000<br />c 101 000<br />d 101 000<br />e 000 110<br />f 000 110<br />g 000 101<br />h 000 101<br />Or taken into account the high order bits, it is reduced to<br />a 10 10<br />b 10 10<br />c 10 01<br />d 10 01<br />e 01 10<br />f 01 10<br />g 01 01<br />h 01 01<br /><br />Thinking about it, this is very taxonomy-like! (such as <A HREF="http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=115366" REL="nofollow">Brachiopoda: Craniata</A>; <A HREF="http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=89593" REL="nofollow">Chordata: Craniata</A>)Salvahttps://www.blogger.com/profile/01062764779798191688noreply@blogger.comtag:blogger.com,1999:blog-19077731.post-73197215863983614332009-04-25T09:31:00.000-05:002009-04-25T09:31:00.000-05:00Interesting post. It occurs to me that a taxonomy ...Interesting post. It occurs to me that a taxonomy could be stored in the same manner.Mike Keeseyhttps://www.blogger.com/profile/00147156174467903264noreply@blogger.com