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Removing broken demo

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svn: r403
This commit is contained in:
Jay McCarthy 2005-07-20 18:40:14 +00:00
parent 035a2a9448
commit e6d8266b44
1 changed files with 0 additions and 71 deletions
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collects/mztake/demos/montecarlo/montecarlo-mztake.ss
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#| The program being debugged (a module in the file "montecarlo.ss") runs
an infinite loop, binding "x" and "y" to a random number between
[-199,199], each iteration.
This is supposed to represent throwing darts at a circular dartboard.
You keep a count of how many darts you have thrown, and a side count
for each time the dart is thrown within the circle. The ratio of
hits to total tries, multiplied by 4, approaches "pi" with some error,
usually closing in around 3.13. The target program does this computation
and binds it to the variable "pi".
This MzTake script visualizes the process, drawing points (darts)
that "hit" the circle, a radius of 200 pixels from the center of
the window. |#
(require (lib "graphics.ss" "graphics"))
#| Needed for open-graphics, open-viewport, and draw-solid-ellipse |#
(open-graphics)
(define window (open-viewport "Debugger" 400 400))
#| This file doesn't animate a list of objects since the number of
objects quickly reaches the thousands (slowing drawing time severly),
and the dots are stationary -- so we just keep drawing the circles at
the random coordinates that we get from the target program.
See the doc for more information on this kind of drawing. |#
(define-mztake-process p ("montecarlo.ss" [x/y/pi-trace 13 13 bind '(x y pi)]))
#| * Create a process to debug montecarlo.ss
* Add a tracepoint at line 13, column 13; in the program,
this is right after the cond determined that the point *is* within
the radius of the circle, before starting the next iteration of the loop.
* At this tracepoint, define "x/y/pi-trace" to a FrTime eventstream that
recieves events containing a list of the latest values of "x" "y" and "pi"
in a list, every time the code at line 13, column 18, is reached. |#
(define x/y/pi (hold x/y/pi-trace))
#| The local, time-varying variable "x/y/pi" is now is a FrTime behavior that always
holds the current (latest) list of values from x/y/pi-trace. |#
(define x (+ 200 (first x/y/pi)))
(define y (+ 200 (second x/y/pi)))
(define current-pi (third x/y/pi))
#| The local, time-varying variables "x" "y" and "current-pi" are bound to
their respective values in the list from x/y/pi. |#
(printf-b "total points chosen: ~a" (count-b (changes x)))
(printf-b "current computed value of pi: ~a" current-pi)
(printf-b "log error: ~a" (log (abs (- current-pi 3.141592653)))) ;; the more negative, the better...
((draw-viewport window) "wheat")
((draw-solid-ellipse window) (make-posn -4 -4) 408 408 "black")
((draw-solid-ellipse window) (make-posn 0 0) 400 400 "sienna")
#| Draw the dartboard |#
(map-e (lambda (x/y) ((draw-solid-ellipse window) (make-posn (first x/y) (second x/y))
3 3 "black"))
(changes (list x y)))
#| Every time the list (x y) changes (x and y get a new value), take this latest list value ("==>")
and pass it to a function which draws a circle at the x,y coordinates in the list. |#
(start/resume p) #| Start the process for montecarlo.ss |#