Galton box animation: Difference between revisions
Content added Content deleted
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;state of simulation...list of all positions and vector of balls (index = bin) |
;state of simulation...list of all positions and vector of balls (index = bin) |
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(define-struct st (poss bins)) |
(define-struct st (poss bins)) |
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; |
;increment vector @i |
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(define (vector-inc- |
(define (vector-inc! v i) (vector-set! v i (add1 (vector-ref v i)))) |
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(let vector-inc-indices ([is is]) |
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(if (null? is) |
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v |
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(begin (vector-set! v (car is) (add1 (vector-ref v (car is)))) |
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| ⚫ | |||
(define BALL-RADIUS 6) |
(define BALL-RADIUS 6) |
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;dead balls have (partition from normal Racket would be useful here...) |
;dead balls have (partition from normal Racket would be useful here...) |
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[dead (filter (λ (p) (>= (pos-row p) height)) new-ps)] |
[dead (filter (λ (p) (>= (pos-row p) height)) new-ps)] |
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; |
;adjust col from [-x,x] to [0,2x] |
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[bin-indices (map (λ (p) (quotient (+ (pos-col p) height) 2)) dead)]) |
[bin-indices (map (λ (p) (quotient (+ (pos-col p) height) 2)) dead)]) |
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;add new balls to the live balls |
;add new balls to the live balls |
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(make-st (append (make-list (random 4) (make-pos 0 0)) live) |
(make-st (append (make-list (random 4) (make-pos 0 0)) live) |
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;sum dead ball positions into bins |
;sum dead ball positions into bins |
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(vector-inc |
(begin (for-each (λ (i) (vector-inc! (st-bins s) i)) bin-indices) |
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| ⚫ | |||
;run simulation with empty list of positions to start, stepping with "tock" and drawing with "draw" |
;run simulation with empty list of positions to start, stepping with "tock" and drawing with "draw" |
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