anchor.diff:                          :n-gibbs 5
                           :segmenter
                           (lambda (cloud)
  -                          (when t #+nil (or (equal 'label (name (chunk1 cloud)))
  -                                            (equal 'label (name (chunk2 cloud))))
  -                                (make-instance 'mnist-dbm-segment-trainer
  -                                               :learning-rate (flt 0.001)
  -                                               :weight-decay
  -                                               (if (conditioning-cloud-p cloud)
  -                                                   (flt 0)
  -                                                   (flt 0.0002))
  -                                               :batch-size 100)))
  +                          (make-instance 'mnist-dbm-segment-trainer
  +                                         :learning-rate (flt 0.001)
  +                                         :weight-decay
  +                                         (if (conditioning-cloud-p cloud)
  +                                             (flt 0)
  +                                             (flt 0.0002))
  +                                         :batch-size 100))
                           :sparser
                           (lambda (cloud chunk)
                             (when (and (member (name chunk) '(f1 f2))
  
positive.code:   (let ((nodes (storage (nodes striped))))
      (loop for image in images
            for stripe upfrom 0
            do (destructuring-bind (image &key omit-label-p sample-visible-p) image
                 (declare (ignore omit-label-p sample-visible-p))
                 (with-stripes ((stripe striped start))
                   (clamp-array image nodes start))))))
  
negative.code:            ;; the key in the cache and what to pass to the dbm. We
             ;; carefully omit labels.
             (list :populate-key #'first
                   :populate-convert-to-dbm-sample-fn
                   (lambda (sample)
                     (list (first sample)
                           :sample-visible-p nil
                           :omit-label-p t))
                   :populate-map-cache-lazily-from-dbm *dbm/2*
                   :populate-periodic-fn
                   (make-instance 'periodic-fn :period 1000
  