#674 Suppressed Atoms in Hash Code

[John May]

branch: suppressed-h-hashcodes

First commit is 'Internal API for suppressing vertices in the hash.'

The additions allow one to suppress the hydrogens in the hashcode without actually removing them from the molecule. Most importantly stereo configuration is preserved. The reason this is beneficial is removing hydrogens must be done with care - particularly in 2D where it could be a wedge/hatch and the only atom defining a chiral centre. If it were removed to persist the correct configuration one must relayout the atoms and assign wedge/hatch bonds. Even if there was a utility to do this it's still nice to get a hash which ignores hydrogens without the original molecule being modified (or cloned).

Probably the nicest example in the test is the hashing of 9 stereo isomers of inositols
one set with implicit hydrogens and one set with explicit hydrogens.

Now I just need to include direct hashing StereoElements... which will be next.

[Egon Willighagen]

A few comments left on GitHub. Here too, I think it's mostly just missing headers. Thanx for producing code with full JavaDoc, unit testing etc.

[John May]

Okay have added another commit with the headers and JavaDoc mistakes resolved.

[Egon Willighagen]

Thanks. Applied and pushed.