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<br><div><div>On Mar 7, 2008, at 2:20 AM, Marguerite Butler wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div>So, please don't use parent to mean ancestor and descendant() to mean grab the entire clade! That will be very confusing. I would prefer the single function, but with the default indicated this way:</div><div><br class="webkit-block-placeholder"></div><div>ancestor(all=FALSE) </div><div>descendant(all=FALSE)</div><div><br></div>If you are coming from the point of view that descendant means direct descendant and ancestor means direct ancestor, this might be more intuitive.</span><br class="Apple-interchange-newline"></blockquote></div><div><br class="webkit-block-placeholder"></div>All I would argue for is to use existing terminology from CS in a consistent way if we are dealing with CS data structures (trees are just a special form of graphs), rather than making up new terminology.<div><br class="webkit-block-placeholder"></div><div>That said, if new terminology already exists anyway and users are used to it, one might as well use that too. Just keep in mind that using ancestors in the sense of direct parents can be highly confusing to users too if those aren't directly biologists (though actually I am a biologist).<br><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>-hilmar<br class="webkit-block-placeholder"></div><div><div> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" face="Monaco" size="3"><span class="Apple-style-span" style="font-size: 11px; ">-- </span></font></div><div><font class="Apple-style-span" face="Monaco" size="3"><span class="Apple-style-span" style="font-size: 11px; ">===========================================================</span></font></div><div><font class="Apple-style-span" face="Monaco" size="3"><span class="Apple-style-span" style="font-size: 11px; ">: Hilmar Lapp -:- Durham, NC -:- hlapp at duke dot edu :</span></font></div><div><font class="Apple-style-span" face="Monaco" size="3"><span class="Apple-style-span" style="font-size: 11px; ">===========================================================</span></font></div><div><font class="Apple-style-span" face="Monaco" size="3"><span class="Apple-style-span" style="font-size: 11px; "><br class="khtml-block-placeholder"></span></font></div><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 11px; "><span class="Apple-style-span" style="font-size: 10px; font-family: Monaco; "></span></span></font></span></span><br class="Apple-interchange-newline"></span></span><br class="Apple-interchange-newline"> </div><br></div></div></body></html>