<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">David,<div class=""><br class=""></div><div class="">I recall 754 discussing the special cases for rootn, but don’t remember if the discrepancy (below) with cfp was mentioned. If it was known and 754 decided its current specification is better, I wouldn’t be inclined to reopen the issue with 754.</div><div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Aug 23, 2018, at 3:34 PM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="Singleton" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;"><div class=""><blockquote type="cite" class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;"><div class=""><blockquote type="cite" class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">rootn -<span class="Apple-converted-space"> </span><br class="">replace cfp rootn(+/-inf,n) with<br class=""></blockquote></div></blockquote><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">I think cfp and 754 agree except for rootn(-inf, n) for even n > 0:</div></div><blockquote class="" style="margin: 0px 0px 0px 40px; border: none; padding: 0px;"><div class=""><br class=""></div><div class="">cfp says it’s the same as rootn(-0, n) for even n < 0 (without div-by-zero), which cfp and 754 both say is +inf.</div><div class="">754 says it's qNaN with invalid.</div></blockquote><div class=""><br class=""></div><div class="">We can ask 754 to review/confirm this case. As usual, cfp needs to match 754. If cfp needs to change this case, it seems better to list out the cases for rootn(+/-inf, n) like 754 does, rather than relay on identity with rootn(+/-0, -n) .</div></div></div></blockquote></div><br class=""></div></body></html>