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Task/Percolation-Mean-cluster-density/EchoLisp/percolation-mean-cluster-density.echolisp

@@ -0,0 +1,37 @@
+(define-constant BLACK  (rgb 0 0 0.6))
+(define-constant WHITE -1)
+;; sets pixels to clusterize to WHITE
+;; returns bit-map vector
+(define (init-C n p )
+    (plot-size n n)
+    (define C (pixels->int32-vector )) ;; get canvas bit-map
+    (pixels-map (lambda (x y) (if (< (random) p) WHITE BLACK )) C)
+    C )
+
+;; random color for new cluster
+(define (new-color)
+    (hsv->rgb (random) 0.9 0.9))
+
+;; make-region predicate
+(define (in-cluster C x y)
+    (= (pixel-ref C x y) WHITE))
+
+;; paint all adjacents to (x0,y0) with new color
+(define (make-cluster C x0 y0)
+                (pixel-set! C x0 y0 (new-color))
+                (make-region in-cluster C x0 y0))
+
+;; task
+(define (make-clusters (n 400) (p 0.5))
+    (define Cn 0)
+    (define C null)
+        (for ((t 5)) ;; 5 iterations
+        (plot-clear)
+        (set!  C (init-C n p))
+        (for* ((x0 n) (y0 n))
+            #:when  (= (pixel-ref C x0 y0) WHITE)
+            (set! Cn (1+ Cn))
+         (make-cluster C x0 y0)))
+
+    (writeln 'n n  'Cn Cn  'density  (// Cn (* n n) 5) )
+    (vector->pixels C)) ;; to screen