Chemical terms for Query structures

Dear support,

Is there a way (preferably in IJChem) to use Chemical Terms to calculate e.g. ring count for a database of query molecules?

 at the moment I get an error message:

Error: Error at molecule with cd_id: 3
Error while evaluating expression:
ringCount()
    Calculation result is not defined for query molecules.

Thanks in advance for your help.

Kind regards,

Anna

The error message "Calculation result is not defined for query molecule." indicates that he input molecule is a query molecule (contains query features), and most of the calculations cannot be performed on query molecules. Calculations which work on query molecules does not throw this exception.

See also this forum topic.

Zsolt

Dear Zsolt,

Thanks for your reply.

I realize that some of the calculations will not work and can not be expected to work. For example I realize calculating MW for a query molecule with A or Q atoms will not work.

However for some query molecules at least some calculations are in principle possible. Example is the attached query where MW, ring count and many other calculations could be performed.

So my question is: Is it possible to run such calculations on query molecules and return errors only for the molecules that contain features making the calculations impossible? Otherwise, do you think you migh add such a functionality in any of the upcoming releases?

Thanks in advance for your help.

Kind regards,

Anna

Dear Anna,

rzepiela wrote:

So my question is: Is it possible to run such calculations on query molecules and return errors only for the molecules that contain features making the calculations impossible? Otherwise, do you think you migh add such a functionality in any of the upcoming releases?

You are right, some query features should not make impossible to calculate certain properties. Unfortunately it is treated on calculator plugin level, not on calculation level, so now TopologyAnalyserPlugin (which contains the ring count function) refuses to calculate any property if the input molecule contains query features.

It can be changed in the future, and we have plans to change it in an upcoming release.

Regards,
Zsolt