anchor.diff:        (do ((tm (- tms 2) (1- tm)))
   	  ((< tm 0))
   	(setf (aref q tm) (aref psi (+ tm 1) (aref q (+ tm 1))))))
  -    (values q prob)))+    (values q prob)))
  
positive.code: 
  (defun split-per-space (str &key (delimiterp #'delimiterp))
    "Split string with specified delimiter."
    (loop :for point = (position-if-not delimiterp str)
       :then (position-if-not delimiterp str :start (1+ end))
       :for end = (and point (position-if delimiterp str :start point))
       :when point :collect (subseq str point end)
       :while end))
  
  (defun make-array-per-space (str)
    "Make an array from a string with words seperated by delimiters."
  
negative.code: (defun pprint-array (stream array)
    "Pretty print routine to print a nested vector."
    (loop
       with first-time = t
       for x across array
       unless first-time
       do (write-char #\Space stream) end
       do (princ x stream)
       (setf first-time nil)))
  
  ;;; And so with a matrix...
  (defun pprint-matrix (stream matrix)
    "Pretty print routine to print a matrix."
    (loop
       for i below (car (array-dimensions matrix))
       do (loop
  	    for j below (cadr (array-dimensions matrix))
  	    do (let ((cell (aref matrix i j)))
  		  (format stream "~a " cell)))
       (format stream "~%")))
  
  