Graphs of bodyweight vs time, Lisp version

bodyweight.lisp

; quick and dirty adaptation from https://gist.github.com/stucchio/1403042
(ql:quickload :numcl)
(ql:quickload :vgplot)

(defparameter *exercise-level* 1.5)
(defparameter *height-inches* (* 6 12))
(defparameter *a* (/ (* *exercise-level* (+ 66 (* 12.7 *height-inches*)))
                     3500.0))
(defparameter *b* (/ (* *exercise-level* 6.23)
                     3500))
(defparameter *g* (/ (* *exercise-level* 6.775)
                     (* 365 3500.0)))

(defparameter *age-range* '(28 40))
(defparameter *t* (numcl:arange (* 365 (first *age-range*))
                                (* 365 (second *age-range*))))

(defun base-weight (consumption time)
  (numcl:/ (numcl:+ (numcl:* *b* (- (numcl:/ consumption 3500.0) *a*))
        (numcl:* *b* *g* time)
        (numcl:- *g*))
     (numcl:* *b* *b*)))

(print (base-weight 3000 (* 25 365)))

(defun weight (time consumption initial-weight)
  (let ((c (numcl:- initial-weight (base-weight consumption time))))
    (numcl:+ (base-weight consumption time)
       (numcl:* c (numcl:exp (numcl:* (numcl:- *b*) (numcl:- time (aref time 0))))))))

(vgplot:plot *t* (base-weight 3500 *t*) "Perfect Balance, 3500 cals"
             *t* (base-weight 3000 *t*) "Perfect Balance, 3000 cals"
             *t* (weight *t* 3500 (base-weight 3000 *t*)) "Paula Deen Fan"
             *t* (weight *t* 3000 (base-weight 3000 *t*)) "Alton Brown Fan"
             )

(defun xticks (tick-locations labels)
  (let ((xtics-data (mapcar (lambda (label location)
                              (uiop:strcat "\"" (write-to-string label) "\" " (write-to-string location)))
                            (coerce labels 'list)
                            (coerce tick-locations 'list))))
    (vgplot:format-plot nil "set xtics (~{~a~^, ~})" xtics-data)
    (vgplot:replot)))

(let ((age-years (numcl:arange (first *age-range*) (1+ (second *age-range*)))))
  (xticks (numcl:* 365 age-years)
          age-years))

(vgplot:xlabel "Age (years)")
(vgplot:ylabel "Bodyweight (lbs)")

(vgplot:axis `(nil ,(* 365 (second *age-range*))))

network_stars.svg

See also https://www.chrisstucchio.com/blog/2011/weight_stability.html for explanation