anchor.diff:     ;; has the same weight.
      :multiplier (/ (length batch)
                     (n-stripes (persistent-chains trainer)))))
  +
  +(require :sb-sprof)
  +
  +(progn
  +  (sb-sprof:reset)
  +  (sb-sprof:start-profiling)
  +  (sleep 10)
  +  (sb-sprof:stop-profiling)
  +  (sb-sprof:report :type :graph))
  +
   |#
  
positive.code:      (linear-at-points 0 1 (* 10 (length *training-images*)) 0
                         (n-inputs trainer))))
  
  (defmethod n-gibbs ((trainer mnist-dbm-trainer))
    (cond ((< (n-inputs trainer) 5000)
           100)
  
negative.code:       (- (max-position (storage (nodes chunk)) start end)
           start))))
  
  (defun make-dbn-reconstruction-misclassification-counters-and-measurers
      (dbn &key (rbm (last1 (rbms dbn))))
    (loop for chunk in (apply #'append
                              (mapcar #'chunks
                                      (subseq (rbms dbn)
                                              0 (1+ (position rbm (rbms dbn))))))
          for measurer = (maybe-make-misclassification-measurer chunk)
          when measurer
          collect (cons (make-instance 'error-counter)
                        measurer)))
  
  (defun make-bm-reconstruction-misclassification-counters-and-measurers (bm)
    (loop for chunk in (chunks bm)
          for measurer = (maybe-make-misclassification-measurer chunk)
          when measurer
          collect (cons (make-instance 'error-counter)
  