(defun nudge (x nval name &optional (distribution *dists*))
 (let*  ((get-val (gethash name distribution))
         (max (dist9-max get-val))
         (min (dist9-min get-val))
         (pd (dist9-distribution get-val))
        ; (tpd (pd-vals pd))
         (cd (cum-array pd))
         (nxp (nudgexp cd x min max (length cd) nval))
         (newval (binrange cd nxp max min (length cd)))) 
   (if (or (< x min) (> x max)) `(x is not in the range) newval)))


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(defun x-bin (x min max b)   ;b = number of bins in distribution, x= # to nudge, *
 (ceiling (+ (/(- x min) (/ (- max min) (- b 1))) 1)))

(defun xpos (cd x min max b) ;xpos finds position of x in cd
           (let ((pval (aref cd (- (x-bin x min max b) 1))))
             (if (= pval 0) `(the x value entered has no frequency) pval)))

(defun nudgexp (cd x min max b nval) ;nval is nudge%
 (let* ((pos (xpos cd x min max b))
       (nmin (- pos (* nval pos)))
       (nmin! (progn
                (let ((fin (aref cd 0)))
                (if (< nmin fin) fin nmin))))
       (nmax (+ pos (* nval pos)))
       (nmax! (progn
                (let ((fin (aref cd (- (length cd) 1))))
                (if (> nmax fin) fin nmax))))
       (prange (make-range :max nmax! :min nmin! :ready? t)))
       (any9 prange)))

(defun bxpos (cd nxp)  ;bin for new xpos
 (loop for n from 0 to (- (length cd) 1)
       if (<= nxp (aref cd n))
       collect (+ n 1) into bin
       finally (return(values (first bin)))))

(defun binsize (max min b)
 (/ (- max min) (- b 1)))

(defun binrange (cd nxp max min b) "Returns random value from within range"
 (let* ((nmin (+ min (* (- (bxpos cd nxp) 2) (binsize max min b))))
        (nmax (+ min (* (- (bxpos cd nxp) 1) (binsize max min b))))
        (nrange (make-range :max nmax :min nmin :ready? t)))
       (any9 nrange)))