<p>I talked with Pari and we decided that the best idea was just to ignore the zero-variance dimensions in the log negative error calculation.  This change has been made in <a href="https://github.com/mlpack/mlpack/commit/4e069ab995e165f1f8c2a707120698cf74cf2f6f" class="commit-link"><tt>4e069ab</tt></a> and should fix your issue, so there should be no more need to add noise.  Let me know if it doesn't and we can reopen the ticket.  Thanks for reporting the issue! :)</p>

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