From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/2317 Path: news.gmane.org!not-for-mail From: Steve Vickers Newsgroups: gmane.science.mathematics.categories Subject: Re: Function composition of natural transformations? Date: Tue, 03 Jun 2003 10:21:49 +0100 Message-ID: <3EDC68AD.6060702@cs.bham.ac.uk> References: <200306021414.QAA18084@d2-hrz.uni-duisburg.de> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241018569 3515 80.91.229.2 (29 Apr 2009 15:22:49 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:22:49 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Tue Jun 3 12:03:04 2003 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 03 Jun 2003 12:03:04 -0300 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 19NDCJ-0001mE-00 for categories-list@mta.ca; Tue, 03 Jun 2003 11:55:35 -0300 User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.3) Gecko/20030312 X-Accept-Language: en-us, en In-Reply-To: <200306021414.QAA18084@d2-hrz.uni-duisburg.de> Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 7 Original-Lines: 21 Xref: news.gmane.org gmane.science.mathematics.categories:2317 Archived-At: Marc Olschok wrote: >For the above reason \circ is used for the "horizontal composition"; >\cdot or \ast (I do not remember which one) is used for the >"vertical composition", which after all looks more "point-wise". > >Unfortunately some authors use these symbols just the other way round. > >Marc > It is also possible to use a 2-dimensional syntax, in which horizontal composition is composed horizontally and vertical composition is composed vertically. Then algebraic manipulations are a bit like sliding tiles around in a tray. Steve Vickers.