File:Animated construction of Sierpinski Triangle.gif
本预览的尺寸：581 × 599像素。 其他分辨率：233 × 240像素 | 465 × 480像素 | 950 × 980像素。
原始文件 （950 × 980像素，文件大小：375 KB，MIME类型：image/gif、循环、10帧、5.0秒）
摘要
本图片使用SageMath创作.
| 描述 |
English: Animated construction of Sierpinski Triangle Self-made. 许可协议I made this with SAGE, an open-source math package. The latest source code lives here, and has a few better variable names & at least one small bug fix than the below. Others have requested source code for images I generated, below. Code is en:GPL; the exact code used to generate this image follows: #***************************************************************************** # Copyright (C) 2008 Dean Moore < dean dot moore at deanlm dot com > # < [email protected] > # # # Distributed under the terms of the GNU General Public License (GPL) # http://www.gnu.org/licenses/ #***************************************************************************** ################################################################################# # # # Animated Sierpinski Triangle. # # # # Source code written by Dean Moore, March, 2008, open source GPL (above), # # source code open to the universe. # # # # Code animates construction of a Sierpinski Triangle. # # # # See any reference on the Sierpinski Triangle, e.g., Wikipedia at # # < http://en.wikipedia.org/wiki/Sierpinski_triangle >; countless others are # # out there. # # # # Other info: # # # # Written in sage mathematical package sage (http://www.sagemath.org/), hence # # heavily using computer language Python (http://www.python.org/). # # # # Important algorithm note: # # # # This code does not use recursion. # # # # More topmatter & documentation probably irrelevant to most: # # # # Inspiration: I viewed it an interesting problem, to try to do an animated # # construction of a Sierpinski Triangle in sage. Thought I'd be lazy & search # # the 'Net for open-source versions of this I could simply convert to sage, but # # the open-source code I found was poorly documented & I couldn't figure it # # out, so I gave up & solved the problem from scratch. # # # # Also, I wanted to animate the construction, which I did not find in # # open-source code on the 'Net. # # # # Comments on algorithm: # # # # The code I found on the 'Net was recursive. I do not much like recursion, # # considering it way for programmers to say, "Look how smart I am! I'm using # # recursion! Aren't I cool?!" I feel strongly recursion is often confusing, # # can chew up too much memory, and should be avoided except when # # # # a) It's unavoidable, or # # b) The code would be atrocious without it. # # # # Did some thinking & swearing, but concocted a non-recursive method, and by # # doing the problem from scratch. Guess it avoids all charges of copyright # # violation, plagiarism, whatever. # # # # More on algorithm via ASCII art. Below we have a given triangle, shaded via # # x's. # # # # The next "generation" is the blank triangles. Sit down & start a Sierpinski # # Triangle on scratch: the next generation is always two on each side of a # # given triangle from the last generation, one on top. Algorithm takes the # # given, shaded triangle (below), and makes the three of the next generation # # arising from it. # # # # See code for more on how this works. # # __________ # # \ / # # \ / # # \ / # # \ / # # _________\/_________ # # \ xxxxxxxxxxxxxxxx / # # \ xxxxxxxxxxxxxx / # # \ xxxxxxxxxxxx / # # \ xxxxxxxxxx / # # _________\ xxxxxxxx /_________ # # \ /\ xxxxxx /\ / # # \ / \ xxxx / \ / # # \ / \ xx / \ / # # \ / \ / \ / # # \/ \/ \/ # # # ################################################################################# # # # Begin program: # # # # First we need three functions; see the below code on how they are used. # # # # The three functions *right_side_triangle* , *left_side_triangle* & # # *top_triangle* are here defined & not as "lambda" functions, as they need # # documented. # # # # I don't care to replicate the poorly-documented code I found on the 'Net. # # # ################################################################################# # # # First function, *right_side_triangle*. # # # # Function *right_side_triangle* gives coordinates of next triangle on right # # side of a given triangle whose coordinates are passed in. # # # # Points *p*, *r*, *q*, *s* & *t* are labeled as passed in: # # # # (p, r)____________________(q, r) # # \ / # # \ / # # \ / # # \ / # # \ (p1, r1)/_________ (q1, r1) # # \ /\ / # # \ / \ / # # \ / \ / # # \ / \ / # # \/ \/ # # (s, t) (s1, t1) # # # # p1 = (q + s)/2, a simple average. # # q1 = q + (q - s)/2 = (3*q - s)/2 # # r1 = (r + t)/2, a simple average. # # s1 = q, easy. # # t1 = t, easy. # # # ################################################################################# def right_side_triangle(p,q,r,s,t): p1 = (q + s)/2 q1 = (3*q - s)/2 r1 = (r + t)/2 s1 = q # A placeholder, solely to make code clear. t1 = t # Ditto, a placeholder. return ((p1,r1),(q1, r1),(s1, t1)) # End of function *right_side_triangle*. ################################################################################# # # # Function *left_side_triangle*: # # # # (p, q) ____________________(q, r) # # \ / # # \ / # # \ / # # \ / # # (p1, r1) _________\ (q1, r1) / # # \ /\ / # # \ / \ / # # \ / \ / # # \ / \ / # # \/ \/ # # (s1, t1) (s, t) # # # # p1 = p - (s - p)/2 = (2p-s+p)/2 = (3p - s)/2 # # q1 = (p + s)/2, a simple average # # r1 = (r + t)/2, a simple average. # # s1 = p, easy. # # t1 = t, easy. # # # ################################################################################# def left_side_triangle(p,q,r,s,t): p1 = (3*p - s)/2 q1 = (p + s)/2 r1 = (r + t)/2 s1 = p # A placeholder, solely to make code clear. t1 = t # Ditto, a placeholder. return ((p1,r1),(q1, r1),(s1, t1)) # End of function *left_side_triangle*. ################################################################################# # # # Function *top_triangle*. # # # # (p1, r1) __________ (q1, r1) # # \ / # # \ / # # \ / # # \ / (s1, t1) # # (p, r)_________\/_________ # # \ xxxxxxxxxxxxxxxx / # # \ xxxxxxxxxxxxxx / (q, r) # # \ xxxxxxxxxxxx / # # \ xxxxxxxxxx / # # \ xxxxxxxx / # # \ xxxxxx / # # \ xxxx / # # \ xx / # # \ / # # \/ # # (s, t) # # # # p1 = (p + s)/2, a simple average. # # q1 = (s + q)/2, a simple average # # r1 = r + (r - t)/2 = (3r - t)/2 # # s1 = s, easy. # # t1 = r, easy. # # # ################################################################################# def top_triangle(p,q,r,s,t): p1 = (p + s)/2 q1 = (s + q)/2 r1 = (3*r - t)/2 s1 = s # Again, both this & next are t1 = r # placeholders, solely to make code clear. return ((p1,r1),(q1, r1),(s1, t1)) # End of function *top_triangle*. ################################################################################# # # # Main program commences: # # # ################################################################################# # Top matter a user may wish to vary: number_of_generations = 8 # How "deep" goes the animation after initial triangle. first_triangle_color = (1,0,0) # First triangle's rgb color as red-green-blue tuple. chopped_piece_color = (0,0,0) # Color of "chopped" pieces as rgb tuple. delay_between_frames = 50 # Time between "frames" of final "movie." figure_size = 12 # Regulates size of final image. initial_edge_length = 3^7 # Initial edge length. # End of material user may realistically vary. Rest should churn without user input. number_of_triangles_in_last_generation = 3^number_of_generations # Always a power of three. images = [] # Holds images of final "movie." coordinates = [] # Holds coordinates. p0 = (0,0) # Initial points to start iteration -- note p1 = (initial_edge_length, 0) # y-values of *p0* & *p1* are the same -- an p2 = ((p0[0] + p1[0])/2, # important book-keeping device. ((initial_edge_length/2)*sin(pi/3))) # Equilateral triangle; see any Internet # reference on these. # We make a polygon (triangle) of initial points: this_generations_image = polygon((p0, p1, p2), rgbcolor=first_triangle_color) images.append(this_generations_image) # Save image from last line. coordinates = [( ( (p0[0] + p2[0])/2, (p0[1] + p2[1])/2 ), # Coordinates ( (p1[0] + p2[0])/2, (p1[1] + p2[1])/2 ), # of second ( (p0[0] + p1[0])/2, (p0[1] + p1[1])/2 ) )] # triangle. # It is *supremely* important # that the y-values of the first two # points are equal -- check definitions # above & code below. this_generations_image = polygon(coordinates[0], # Image of second triangle. rgbcolor=chopped_piece_color) images.append(images[0] + this_generations_image) # Save second image, tacked on top of first.
# Now the loop that makes the images:
number_of_triangles_in_this_generation = 1 # We have made one "chopped" triangle, the second, above.
while number_of_triangles_in_this_generation < number_of_triangles_in_last_generation:
this_generations_image = Graphics() # Holds next generation's image, initialize.
next_generations_coordinates = [] # Holds next generation's coordinates, set to null.
for a,b,c in coordinates: # Loop on all triangles.
(p, r) = a # Right point; note y-value of this & next are equal.
(q, r1) = b # Left point; note r1 = r & thus *r1* is irrelevant;
# it's only there for book-keeping.
(s, t) = c # Bottom point.
# Now construct the three triangles & their three polygons of the next
# generation.
right_triangle = right_side_triangle(p,q,r,s,t) # Here use those
left_triangle = left_side_triangle (p,q,r,s,t) # utility functions
upper_triangle = top_triangle (p,q,r,s,t) # defined at top.
right = polygon(right_triangle, rgbcolor=(chopped_piece_color)) # Make next
left = polygon(left_triangle, rgbcolor=(chopped_piece_color)) # generation's
top = polygon(upper_triangle, rgbcolor=(chopped_piece_color)) # triangles.
this_generations_image = this_generations_image + (right + left + top) # Add image.
next_generations_coordinates.append(right_triangle) # Save the coordinates
next_generations_coordinates.append( left_triangle) # of triangles of the
next_generations_coordinates.append(upper_triangle) # next generation.
# End of "for a,b,c" loop.
coordinates = next_generations_coordinates # Save for next generation.
images.append(images[-1] + this_generations_image) # Make next image: all previous
# images plus latest on top.
number_of_triangles_in_this_generation *= 3 # Bump up.
# End of *while* loop.
a = animate(images, figsize=[figure_size, figure_size], axes=False) # Make image, ...
a.show(delay = delay_between_frames) # Show image.
# End of program.
End of code. |
| 日期 |
2008年3月23日 (原始上传日期) |
| 来源 | 自己的作品 (Original text: self-made) |
| 作者 | (Original text: dino (talk)) |
许可协议
本文件采用知识共享署名-相同方式共享 3.0 未本地化版本许可协议授权。
- 您可以自由地：
- 共享 – 复制、发行并传播本作品
- 修改 – 改编作品
- 惟须遵守下列条件：
- 署名 – 您必须对作品进行署名，提供授权条款的链接，并说明是否对原始内容进行了更改。您可以用任何合理的方式来署名，但不得以任何方式表明许可人认可您或您的使用。
- 相同方式共享 – 如果您再混合、转换或者基于本作品进行创作，您必须以与原先许可协议相同或相兼容的许可协议分发您贡献的作品。
|
已授权您依据自由软件基金会发行的无固定段落及封面封底文字（Invariant Sections, Front-Cover Texts, and Back-Cover Texts）的GNU自由文件许可协议1.2版或任意后续版本的条款，复制、传播和／或修改本文件。该协议的副本请见“GNU Free Documentation License”。 |
您可以选择您需要的许可协议。
原始上传日志
The original description page was here. All following user names refer to en.wikipedia.
- 2008-03-23 18:33 Dino 1200×1200×7 (344780 bytes) {{Information |Description=Animated construction of Sierpinski Triangle |Source=self-made |Date=March 23, 2008 |Location=Boulder, Colorado |Author=~~~ |other_versions= }} Self-made. Will post source code later.
文件历史
点击某个日期/时间查看对应时刻的文件。
| 日期/时间 | 缩略图 | 大小 | 用户 | 备注 | |
|---|---|---|---|---|---|
| 当前 | 2011年2月10日 (四) 02:41 | | 950 × 980（375 KB） | Deanmoore | Seemingly better version |
| 2008年4月12日 (六) 20:34 |  | 1,200 × 1,200（337 KB） | יוסי | {{Information |Description={{en|Animated construction of Sierpinski Triangle<br/> Self-made. == Licensing: == I made this with SAGE, an open-source math package. The latest source code lives [h |
文件用途
以下页面使用本文件：
全域文件用途
以下其他wiki使用此文件：
- ar.wikipedia.org上的用途
- bg.wikipedia.org上的用途
- ca.wikipedia.org上的用途
- ckb.wikipedia.org上的用途
- el.wikipedia.org上的用途
- en.wikipedia.org上的用途
- es.wikipedia.org上的用途
- fa.wikipedia.org上的用途
- he.wikipedia.org上的用途
- hi.wikipedia.org上的用途
- ja.wikipedia.org上的用途
- kn.wikipedia.org上的用途
- pl.wikipedia.org上的用途
- pt.wikipedia.org上的用途
- ru.wikipedia.org上的用途
- ru.wiktionary.org上的用途
- sr.wikipedia.org上的用途
- sv.wikipedia.org上的用途
- uk.wikipedia.org上的用途
- www.wikidata.org上的用途
