Matched Pairs Detector - can't view full table

When I use the MPD node, the table doesn't show Row1 (or at least is labelling the first row Row2), and when I try to enlarge the default window size, the data is blanked out.

Data that I can see looks OK. See screenshots and debug log attached.

Erl Wood 2.3.1 nightly build
KNIME 2.5.1
tested  Linux-64, Mac OS (10.6.8), WinXP-64 (KNIME32)


(the other) Simon

Hi other Simon,

I think I know the solution for this.

In your KNIME client go to File-->Preferences-->KNIME-->Chemistry and choose the Chemaxon Molecule renderer as the prefered one for Smiles and Rxn.

Let me know if that works.


Smiles strings get rendered as structures, but still the same problem of the table disappearing if I try to re-size the window.

Have you also used the Chemaxon Molecule renderer  for Rxn columns too?


Of course.


On the other hand, setting all the render options to 'string' restores functionality of window re-sizing.

Setting the renderer to either Marvin or Indigo causes the table to disappear if the window is re-sized.

At least I have a work-around for now.

Yeah this problem has been around for ages now.  

Hi Simon,

The error indicates a problem with the renderer. I suspect that the node produces an "illegal" rxn tranformation that makes the renderer crash.

Can you please post here the list of the dummy molecules you used to calculate the pairs?

I'll try to reproduce the problem and find the cause.


Here are the fiendishly complex test molecules that I have been using:



Good luck!

Hi again,

I tested in on Win64 with KNIME 2.5.1 and the latest community updates.

The Marvin Rxn renderer crashes when you try to open the window. However the indigo rxn renderer works just fine. (see attachment).



Yay! With last night's updates, the Indigo renderer is now working for me.

Thanks George,


(the other) Simon