I think that when updating weights, should not target all nodes. about simpsom

[fcomitani]

Hello @cuiguohua,

the radius of the Gaussian is determined by the sigma which is reduced at every step by update_sigma, thus effectively reducing the neighborhood set.

You are however right about the Gaussian being always > 0, unless the sigma gets infinitely small.
I haven't looked at the code in a while and I'm not sure why I put that condition. Possibly it was just a debugging device which forgot to remove.

Just let me think it over and do a couple of extra tests. If I still can't find a justification for its presence I will remove it in the next version.

Thanks.

[fcomitani]

The redundant condition was removed, I'm closing this issue.