Hi John, The en-us-g2.ctb back-translation works very well so it would be great to have some documentation so that we can fix some problems in some of the other translators. There are a few things I've noticed in which en-us-g2.ctb should be easily fixed sometime: 1. Dates such as 03/19/09. This forward translates as #jc/ai/ji, but on back-translation the slashes turn into st, giving: 03st19st09. Actually I looked up dates in the BANA Braille Codes Update 2007 and in the update for 2.7e (Page L22) they say 4-5-6 3-4 should be used for slashes in dates. 2. Simple fractions such as 1/2 have the same problem as dates. Here the 2007 update says that when the numerator is above the denominator, 3-4 should be used on its own. If they are on the same level then 4-5-6 3-4 should be used. 3. A problem caused by ambiguities in braille but for which an exception could be used is a.m. and p.m. as used in 12-hour times such as 2:30 a.m. Of course they can be in upper case as A.M. and P.M too. Forward translation of a.m. correctly gives a4m4 and p.m. gives p4m4 but, of course, back-translation results in addm. and pddm. What would be the best way to add exceptions for these that would work for both the lower and upper case scenarios? 4. The pound sterling symbol is not translated correctly in either direction. In braille it should appear as dots 1-2-3 in front of the number sign. It is currently appearing as an extra number sign. 5. The euro sign is not recognised. 6. The cents sign is forward-translated correctly but back-translates as c-cedilla. Anyway, that's all I've found so far. Jonathan -----Original Message----- From: liblouis-liblouisxml-bounce@xxxxxxxxxxxxx [mailto:liblouis-liblouisxml-bounce@xxxxxxxxxxxxx] On Behalf Of John J. Boyer Sent: Thursday, 19 March 2009 4:17 a.m. To: liblouis-liblouisxml@xxxxxxxxxxxxx Subject: [liblouis-liblouisxml] Re: Backtranslation and use of classes Michel, Thanks for the information and example. The change to the code to handle back-translation when classes are used may be quite simple. Back-translation is actually simpler and faster than forward translation. The tables do have to be tweaked to get good results. I'm trying to remember what I did for the en-us-g2.ctb table, So I can write some documentation. John On Wed, Mar 18, 2009 at 11:03:42AM +0100, Michel Such wrote: > Hi John, > > As Jonathan pointed out, there seems to be a problem with backtranslation > and tables that use classes. > > Let's take an example: > > In the table fr-bfu-g2.ctb, there is a class called con that contains all > consonnants. > > To contract the sequence of letters "er" we have 2 rules: > before con midword er 236 > endword 236 > > This works fine in forward translation. > When backtranslating the "er" sequence placed inside a word before a > consonnant is not reversed to "er". > > If you replace the 2 rules by this one: > midendword er 236 > it is not perfect in forward translation, which is normal, but works fine > in any case in backtranslation. > So the problem really seems bo be with classes. > I imagine that backtranslation from grade 2 is a complexe job. > > Michel Such > > > For a description of the software and to download it go to > http://www.jjb-software.com -- My websites: GodTouches Digital Ministry, Inc. http://www.abilitiessoft.com/godtouches Abilitiessoft, Inc. http://www.abilitiessoft.com Location: Madison, WI, USA For a description of the software and to download it go to http://www.jjb-software.com __________ Information from ESET NOD32 Antivirus, version of virus signature database 3946 (20090318) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __________ Information from ESET NOD32 Antivirus, version of virus signature database 3946 (20090318) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com For a description of the software and to download it go to http://www.jjb-software.com