June 2018 Update

Task/Sierpinski-triangle-Graphical/Python/sierpinski-triangle-graphical-1.py

@@ -1,20 +1,9 @@
-#!/usr/bin/env python
-##########################################################################################
-# import necessary modules
-# ------------------------
-from numpy import *
-import turtle
-
-##########################################################################################
-#	Functions defining the drawing actions
-#       (used by the function DrawSierpinskiTriangle).
-#	----------------------------------------------
-def Left(turn, point, fwd, angle, turt):
-	turt.left(angle)
-	return [turn, point, fwd, angle, turt]
-def Right(turn, point, fwd, angle, turt):
-	turt.right(angle)
-	return [turn, point, fwd, angle, turt]
-def Forward(turn, point, fwd, angle, turt):
-	turt.forward(fwd)
-	return [turn, point, fwd, angle, turt]
+# likely the simplest possible version?
+import turtle as t
+def sier(n,length):
+    if (n==0):
+        return
+    for i in range(3):
+        sier(n-1, length/2)
+        t.fd(length)
+        t.rt(120)

Task/Sierpinski-triangle-Graphical/Python/sierpinski-triangle-graphical-2.py

@@ -1,60 +1,21 @@
+#!/usr/bin/env python
 ##########################################################################################
-#		The drawing function
-#		--------------------
-#
-# level		level of Sierpinski triangle (minimum value = 1)
-# ss		screensize (Draws on a screen of size ss x ss. Default value = 400.)
-#-----------------------------------------------------------------------------------------
-def DrawSierpinskiTriangle(level, ss=400):
-	# typical values
-	turn = 0		# initial turn (0 to start horizontally)
-	angle=60.0 		# in degrees
+# a very complicated version
+# import necessary modules
+# ------------------------
+from numpy import *
+import turtle
 
-	# Initialize the turtle
-	turtle.hideturtle()
-	turtle.screensize(ss,ss)
-	turtle.penup()
-	turtle.degrees()
-
-	# The starting point on the canvas
-	fwd0         = float(ss)
-	point=array([-fwd0/2.0, -fwd0/2.0])
-
-	# Setting up the Lindenmayer system
-	# Assuming that the triangle will be drawn in the following way:
-	#	1.) Start at a point
-	#	2.) Draw a straight line - the horizontal line (H)
-	#	3.) Bend twice by 60 degrees to the left (--)
-	#	4.) Draw a straight line - the slanted line (X)
-	#	5.) Bend twice by 60 degrees to the left (--)
-	#	6.) Draw a straight line - another slanted line (X)
-	# 		This produces the triangle in the first level. (so the axiom to begin with is H--X--X)
-	#	7.) For the next level replace each horizontal line using
-	#		X->XX
-	#		H -> H--X++H++X--H
-	#			The lengths will be halved.
-
-
-	decode    = {'-':Left, '+':Right, 'X':Forward, 'H':Forward}
-	axiom     = 'H--X--X'
-
-	# Start the drawing
-	turtle.goto(point[0], point[1])
-	turtle.pendown()
-	turtle.hideturtle()
-	turt=turtle.getpen()
-	startposition=turt.clone()
-
-	# Get the triangle in the Lindenmayer system
-	fwd       = fwd0/(2.0**level)
-	path      = axiom
-	for i in range(0,level):
-		path=path.replace('X','XX')
-		path=path.replace('H','H--X++H++X--H')
-
-	# Draw it.
-	for i in path:
-		[turn, point, fwd, angle, turt]=decode[i](turn, point, fwd, angle, turt)
 ##########################################################################################
-
-DrawSierpinskiTriangle(5)
+#	Functions defining the drawing actions
+#       (used by the function DrawSierpinskiTriangle).
+#	----------------------------------------------
+def Left(turn, point, fwd, angle, turt):
+	turt.left(angle)
+	return [turn, point, fwd, angle, turt]
+def Right(turn, point, fwd, angle, turt):
+	turt.right(angle)
+	return [turn, point, fwd, angle, turt]
+def Forward(turn, point, fwd, angle, turt):
+	turt.forward(fwd)
+	return [turn, point, fwd, angle, turt]

Task/Sierpinski-triangle-Graphical/Python/sierpinski-triangle-graphical-3.py

@@ -0,0 +1,60 @@
+##########################################################################################
+#		The drawing function
+#		--------------------
+#
+# level		level of Sierpinski triangle (minimum value = 1)
+# ss		screensize (Draws on a screen of size ss x ss. Default value = 400.)
+#-----------------------------------------------------------------------------------------
+def DrawSierpinskiTriangle(level, ss=400):
+	# typical values
+	turn = 0		# initial turn (0 to start horizontally)
+	angle=60.0 		# in degrees
+
+	# Initialize the turtle
+	turtle.hideturtle()
+	turtle.screensize(ss,ss)
+	turtle.penup()
+	turtle.degrees()
+
+	# The starting point on the canvas
+	fwd0         = float(ss)
+	point=array([-fwd0/2.0, -fwd0/2.0])
+
+	# Setting up the Lindenmayer system
+	# Assuming that the triangle will be drawn in the following way:
+	#	1.) Start at a point
+	#	2.) Draw a straight line - the horizontal line (H)
+	#	3.) Bend twice by 60 degrees to the left (--)
+	#	4.) Draw a straight line - the slanted line (X)
+	#	5.) Bend twice by 60 degrees to the left (--)
+	#	6.) Draw a straight line - another slanted line (X)
+	# 		This produces the triangle in the first level. (so the axiom to begin with is H--X--X)
+	#	7.) For the next level replace each horizontal line using
+	#		X->XX
+	#		H -> H--X++H++X--H
+	#			The lengths will be halved.
+
+
+	decode    = {'-':Left, '+':Right, 'X':Forward, 'H':Forward}
+	axiom     = 'H--X--X'
+
+	# Start the drawing
+	turtle.goto(point[0], point[1])
+	turtle.pendown()
+	turtle.hideturtle()
+	turt=turtle.getpen()
+	startposition=turt.clone()
+
+	# Get the triangle in the Lindenmayer system
+	fwd       = fwd0/(2.0**level)
+	path      = axiom
+	for i in range(0,level):
+		path=path.replace('X','XX')
+		path=path.replace('H','H--X++H++X--H')
+
+	# Draw it.
+	for i in path:
+		[turn, point, fwd, angle, turt]=decode[i](turn, point, fwd, angle, turt)
+##########################################################################################
+
+DrawSierpinskiTriangle(5)