How much does your giant weigh?

height-mass.el

(defun height-mass (start-height start-mass end-height build-ratio)
  "How much does your giant weigh? 
Calculate from START-HEIGHT, START-MASS, and END-HEIGHT multiplied by 
BUILD-RATIO the END-MASS.  BUILD-RATIO is a factor to express the difference
in build between different creatures.  (The factor for a dwarf might be 2.25, 
225% heavier than normal.)  
Formula: end-mass = start-mass * (end-height / start-height)^3
See: 
https://en.wikipedia.org/wiki/Square%E2%80%93cube_law
https://www.enworld.org/threads/how-much-does-my-giant-weight.106631/post-1846443"
  (interactive "nStarting Height? \nnStarting Mass? \nnEnd Height? \nnBuild Ratio? ")
  (let* ((start-height (* 1.0 start-height)) ; make measurements floats.
         (start-mass (* 1.0 start-mass))
         (end-height (* 1.0 end-height))
         (ratio (expt (/ end-height start-height) 3))
         (end-mass (* start-mass ratio)))
    (message "Start Height: %g; Start Mass: %g; End Height: %g; Build Ratio: %g
Ratio: %g; End Mass: %g; * Build Ratio: %g"
             start-height start-mass end-height build-ratio
             ratio end-mass (* build-ratio end-mass))))