220 19167 article Path: news.gmane.org!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Point class Date: Wed, 22 Jul 2015 13:29:27 -0400 Lines: 28 Approved: news@gmane.org Message-ID: References: Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1437586196 9258 80.91.229.3 (22 Jul 2015 17:29:56 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 22 Jul 2015 17:29:56 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC37LBFWUIFBBAVGX6WQKGQEY2PLJJQ@isocpp.org Wed Jul 22 19:29:40 2015 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-lb0-f200.google.com ([209.85.217.200]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ZHxpr-0006Qy-SJ for gclcip-std-proposals@m.gmane.org; Wed, 22 Jul 2015 19:29:39 +0200 Original-Received: by lbcjf8 with SMTP id jf8sf59367354lbc.0 for ; Wed, 22 Jul 2015 10:29:39 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:to:from:subject:date:lines:message-id:references :mime-version:content-type:content-transfer-encoding:user-agent :in-reply-to:x-original-sender:x-original-authentication-results :reply-to:precedence:mailing-list:list-id:x-spam-checked-in-group :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=Bxz55eRhCHF/dNQii6CeeOQN4oJRNzO6CTi6ij+oA14=; b=eJhtoUj7IRof9vHq6Wwpadk7xldr2nNuzfve/tEjgw/+gkoaFmbvwa0Xi1GdMq2xFX WzfKhAiZPt5Mp6KFX7+P2Q/uPUuIte8ARvG2N0YB18SyWctjuZ4WJNau9SHdS/fhKQLm Vbo8jTOyoDD6ftPqCxUph77UGOrhy2OWMnK4csxOyFUtDNV9fg8CfksS2ywOH34EzszQ 3ZizGzv88OX/061s7gKFtgXqaKAFiFyEag9s1OgMnLdljhXc5rsz5xEkD2uaSbm0Z8mS tH7JG8a9+VCgq9wX5ccyBR2PPlBbHbtLJXPPG5RDqASSUkZITfU X-Gm-Message-State: ALoCoQmjRoUQYLaML3Pd1n+yv89oyIy1YTmtfOrBRFnMeWbS3xvx1U6HsrydJXzNHJOWzqP+e/oB X-Received: by 10.194.173.3 with SMTP id bg3mr1671862wjc.5.1437586179456; Wed, 22 Jul 2015 10:29:39 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.152.87.146 with SMTP id ay18ls107331lab.20.gmail; Wed, 22 Jul 2015 10:29:38 -0700 (PDT) X-Received: by 10.152.2.2 with SMTP id 2mr3506292laq.58.1437586178009; Wed, 22 Jul 2015 10:29:38 -0700 (PDT) Original-Received: from plane.gmane.org (plane.gmane.org. [80.91.229.3]) by mx.google.com with ESMTPS id l7si1731583lae.121.2015.07.22.10.29.37 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 22 Jul 2015 10:29:37 -0700 (PDT) Received-SPF: pass (google.com: domain of gclcip-std-proposals@m.gmane.org designates 80.91.229.3 as permitted sender) client-ip=80.91.229.3; Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1ZHxpn-0006Ot-5W for std-proposals@isocpp.org; Wed, 22 Jul 2015 19:29:35 +0200 Original-Received: from tripoint.kitware.com ([66.194.253.20]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 22 Jul 2015 19:29:35 +0200 Original-Received: from mwoehlke.floss by tripoint.kitware.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 22 Jul 2015 19:29:35 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 16 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: tripoint.kitware.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 In-Reply-To: X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of gclcip-std-proposals@m.gmane.org designates 80.91.229.3 as permitted sender) smtp.mail=gclcip-std-proposals@m.gmane.org; dmarc=fail (p=NONE dis=NONE) header.from=gmail.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:19167 Archived-At: On 2015-07-22 13:19, David Haim wrote: > 2) After digging a bit in the Eigen library, I couldn't find an explicit > Point class, are you sure they have implemented such class? Yes and no; see the vector class(es). There's not much=C2=B9 benefit to defining a point class vs. a vector class, and a general vector has more uses. A "point" is just a vector offset from the origin, which is merely a semantic distinction; it's fairly common to treat "points" as a semantic subset of "vectors". (=C2=B9 Actually, offhand I can't think of *any* benefit except maybe type distinction, and strong typedefs would make that moot. I feel like *maybe* there is some benefit, but I can't think what.) --=20 Matthew --=20 ---=20 You received this message because you are subscribed to the Google Groups "= ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposa= ls/. .