;"plottest.scm" test charplot.scm
;Copyright (C) 1992 Aubrey Jaffer
;
;Permission to copy this software, to modify it, to redistribute it,
;to distribute modified versions, and to use it for any purpose is
;granted, subject to the following restrictions and understandings.
;
;1.  Any copy made of this software must include this copyright notice
;in full.
;
;2.  I have made no warranty or representation that the operation of
;this software will be error-free, and I am under no obligation to
;provide any services, by way of maintenance, update, or otherwise.
;
;3.  In conjunction with products arising from the use of this
;material, there shall be no use of my name in any advertising,
;promotional, or sales literature without prior written consent in
;each case.

(require 'charplot)
(require 'random)
(require 'random-inexact)

(define strophoid
  (let ((l '()))
    (do ((x -1.0 (+ x 0.05)))
	((> x 4.0))
      (let* ((a (/ (- 2 x) (+ 2 x))))
	(if (>= a 0.0)
	    (let* ((y (* x (sqrt a))))
	      (set! l (cons (cons x y) l))
	      (set! l (cons (cons x (- y)) l))))))
    l))
(plot strophoid "x" "y") (newline)

(histograph (do ((idx 99 (+ -1 idx))
		 (lst '() (cons (* .02 (random:normal)) lst)))
		((negative? idx) lst))
	    "normal")
(newline)

(histograph (do ((idx 99 (+ -1 idx))
		 (lst '() (cons (random 5) lst)))
		((negative? idx) lst))
	    "random")
(newline)