On Friday 27 April 2007, Nina Jeliazkova wrote: > Here is the story. > 1) Create (somehow) a structure as IMolecule (e.g. benzene with > alternating single/double bonds) > 2) Run HueckelAromaticityDetector to perceive aromaticity > 3) Write the structure into CML > 4) Read the structure back from CML into a new IMolecule > 5) Now the new IMolecule has bond orders 1.5 , while the origin one as in > 1) has bond orders 1.0 and 2.0
Ah... that sounds like a bug. CDK in the early days used 1.5 bond order == an aromatic bond, but drop that in favour of IBond.setFlag(CDKConstancs.ISAROMATIC). Seems that the CMLReader has not been updated. > This doesn't break isomorphism test and fingerprints, but does break atom > types recognition as per HybridizationStateATMatcher. In this example, > atom types of the original molecule will be C.sp2, while in the new > molecule will be Caromatic.sp2. Atom type perception is a tricky thing indeed. What suprises me that the first type is not aromatic too! Because you did do atomiticity detection. Actually, since the atom type list contains the the concept of aromaticity, it must be done prior to calling the perception tool. Maybe a second bug? > Not sure this breaks anything else than my atom environments code, but I am > wondering what's the best way to handle the issue. > > Attached is JUnit test. Thanx! I have filed it in the bug track system, so that it can soon be fixed (by the first who has time for it). Egon -- [EMAIL PROTECTED] Blog: http://chem-bla-ics.blogspot.com/ GPG: 1024D/D6336BA6 ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Cdk-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/cdk-user
