From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.help Subject: Re: distance from Easter Island to Chile Date: Mon, 21 Apr 2014 04:16:49 +0200 Organization: Aioe.org NNTP Server Message-ID: <87tx9ns9ym.fsf@nl106-137-194.student.uu.se> References: <87mwfguasr.fsf@nl106-137-194.student.uu.se> <87mwfg823s.fsf@nl106-137-194.student.uu.se> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1398046825 25694 80.91.229.3 (21 Apr 2014 02:20:25 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 21 Apr 2014 02:20:25 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon Apr 21 04:20:20 2014 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Wc3qF-00075N-Jn for geh-help-gnu-emacs@m.gmane.org; Mon, 21 Apr 2014 04:20:19 +0200 Original-Received: from localhost ([::1]:47260 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wc3qF-0005g9-49 for geh-help-gnu-emacs@m.gmane.org; Sun, 20 Apr 2014 22:20:19 -0400 Original-Path: usenet.stanford.edu!news.tele.dk!news.tele.dk!small.news.tele.dk!newsfeed.xs4all.nl!newsfeed3a.news.xs4all.nl!xs4all!news.stack.nl!aioe.org!.POSTED!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 37 Original-NNTP-Posting-Host: VVbyYd/iFZoeWNmD9i++cQ.user.speranza.aioe.org Original-X-Complaints-To: abuse@aioe.org User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-Notice: Filtered by postfilter v. 0.8.2 Cancel-Lock: sha1:JNCWjzdkfYZGPP0UABHUwL6qFbE= Mail-Copies-To: never Original-Xref: usenet.stanford.edu gnu.emacs.help:205016 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:97281 Archived-At: giacomo.boffi@gmail.com writes: > (progn (defun d2r (x) (/ (* pi x) 180)) ... Aha, degrees-to-radians is a macro, won't play with mapcar (?). Did some improvements (I hope) to the interface: (defun d2r (d) (/ (* pi d) 180)) (defun spherical-law-of-cosines (p1 p2) (let ((lat1 (car p1)) (lon1 (cadr p1)) (lat2 (car p2)) (lon2 (cadr p2))) (acos (+ (* (sin lat1) (sin lat2)) (* (cos lat1) (cos lat2) (cos (- lon2 lon1))))))) (defun distance-2 (p1 p2) (let*((from (car p1)) (from-coords-r (mapcar 'd2r (cadr p1))) (to (car p2)) (to-coords-r (mapcar 'd2r (cadr p2))) (dist (* 6378.1 (spherical-law-of-cosines from-coords-r to-coords-r)) )) (message (format "%s -> %s: %8.2f km" from to dist)) )) (setq p1 '("Santiago" (33.4500 70.6667))) (setq p2 '("Easter Island" (27.1167 109.3667))) (distance-2 p1 p2) Now we just need a database of locations, then we can really go nuts... -- underground experts united: http://user.it.uu.se/~embe8573