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Talk:Stellation

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apparently unaware that it was not consistent with Kepler. For example one of his fifty-nine icosahedra is just a loose gaggle of small shards floating in space and entirely disconnected from each other: hardly an "extension" of a core figure which is not even present. Technically one could say that a "stellation diagram" of a polygon is a set of collinear points with some segments drawn in, but it is pretty trivial and non-encyclopedic. If you want to explore them for yourself then I would suggest a uniform or quasiregular polygon, since it has two (alternating) kinds of edge, but I will not be discussing further anything non-encyclopedic. — Cheers,
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point. In fact it specifically says that the {6,2} is two triangles, which is shown. The problem with the 9-gon is that the caption says the {9,3} is three triangles, yet none of the pictures with the coloured areas are anything but variations on the {9,4}. If, as the caption says, the {9,3} is three triangles, then where are the three triangles in the picture labelled as {9,3}??
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I guess I'm just a bit confused about the designation {9/2} etc. I can see how having 9 points and going to the 4th one around can make the star shape shown, but why is the same shape shown with different numbers? All the shapes are {9/4}, just coloured differently. The examples with 7 sided shapes
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Here are two examples of stellations of an octagon. I say "truncated square" rather than octagon because I wanted half symmetry, 2 types of edges to stellate, but unsure if that's really needed in these cases. I colored edges green and purple that represent the boundary of the stellation and showed
387:(technically the black lines extend to infinity). The enneagon is the coloured bit in the middle. Either the accompanying caption should make this clear (and the stellation diagrams made less prominent through thinning), or the stellation diagrams removed and just the enneagons left in. — Cheers, 303:
This is another area where it is easy to be misled by bright ideas and poor resources. Coxeter's treatment of stellation was fundamentally different from his predecessors - Bradwardine, Kepler, Poinsot, Cauchy, Cayley. This has not been helped by Coxeter's use of their definition before blithely
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it is a process to construct new poligons ( in two dimensions) and to construct new polyhedra in three dimensions. The process consist in extending the facial planes of the polyhedron untill they meet each other...the resulting polyhedron is the new stellated polyhedron. by IP 194.183.69.146 at
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Thanks for the efforts, but the caption still doesn't seem to fit in with the examples to the left. On the left example, there are pictures showing how each n-gon is formed. It is clear how the numbers in braces show the total number of points and the number skipped to get to the next connected
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My primary interest if I support including something is to aid understanding of the 3D stellations, so if its trivial, that makes it a good candidate for teaching something new. But I admit the messy disconnected stellations (59 icosahedra) never much attracted me, only those that showed the
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the sides or faces continuously from the original. Wheeler studied stellation diagrams more closely and observed the way that the face planes divided space into cells, whose edges are segments of the lines of intersection. Coxeter then took this cell-based approach to its logical conclusion,
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It seems like stellation of polygons ought to work like stellations of polyhedra. In polyhedra there's one face plane (stellation diagram) for every type of face, and each shows all the intersection boundaries, and each domain can be ON or OFF. In polygons, or especially regular polygons, a
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Yes, The star polygons named {9/p} are the colored ones with the full stellation, the black one. Maybe it would be more clear if the black edges were recolored to be less prominent as lighter gray?
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stellation diagram is a line with intersection points dividing domains. So a general polygonal stellation ought to have some sort of binary ON/OFF for each segment between points.
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The confusion arises because the graphic is misleading. The Large black-lined figure repeated four times is not the enneagon itself but the
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presenting his own work as if it were consistent. Bradwardine studied only cyclic polygons, Kepler expanded the idea to polyhedra by
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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going around at different rates make perfect sense. Can any one explain??
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I have clarified the caption a bit. Any better? — Cheers,
187:, a collaborative effort to improve the coverage of 101:, a collaborative effort to improve the coverage of 326:relations to the regular polyhedra and compounds. 229:This article has not yet received a rating on the 257:Stellation of polygons? (1D stellation diagrams?) 511:Participate in the deletion discussion at the 401:I lightened the outline, maybe that'll help. 8: 152: 47: 154: 49: 19: 554:Unknown-importance Polyhedra articles 7: 481:Thank you. Now corrected. — Cheers, 181:This article is within the scope of 95:This article is within the scope of 38:It is of interest to the following 277:the linear diagrams on the bottom 14: 544:Mid-priority mathematics articles 115:Knowledge:WikiProject Mathematics 292: 174: 156: 118:Template:WikiProject Mathematics 82: 72: 51: 20: 209:Knowledge:WikiProject Polyhedra 135:This article has been rated as 506:Academ Stellated dodecagon.svg 212:Template:WikiProject Polyhedra 1: 525:11:08, 13 February 2019 (UTC) 491:11:40, 23 November 2015 (UTC) 476:09:01, 23 November 2015 (UTC) 451:It looks like small mistake: 203:and see a list of open tasks. 109:and see a list of open tasks. 539:C-Class mathematics articles 336:20:22, 6 February 2015 (UTC) 319:12:28, 6 February 2015 (UTC) 287:22:57, 5 February 2015 (UTC) 272:22:31, 5 February 2015 (UTC) 570: 549:C-Class Polyhedra articles 446:05:15, 18 April 2015 (UTC) 431:17:29, 17 April 2015 (UTC) 411:11:27, 13 March 2015 (UTC) 397:10:11, 13 March 2015 (UTC) 375:09:51, 13 March 2015 (UTC) 360:04:08, 13 March 2015 (UTC) 231:project's importance scale 228: 169: 134: 67: 46: 461:The enneagon (nonagon) { 453:The enneagon (nonagon) { 253:03:44, February 7, 2003 141:project's priority scale 98:WikiProject Mathematics 28:This article is rated 184:WikiProject Polyhedra 121:mathematics articles 459:. I think, must be: 342:Graphic of enneagon 517:Community Tech bot 385:stellation diagram 215:Polyhedra articles 90:Mathematics portal 34:content assessment 245: 244: 241: 240: 237: 236: 151: 150: 147: 146: 561: 296: 217: 216: 213: 210: 207: 178: 171: 170: 160: 153: 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 569: 568: 564: 563: 562: 560: 559: 558: 529: 528: 513:nomination page 499: 344: 259: 250: 214: 211: 208: 205: 204: 120: 117: 114: 111: 110: 88: 81: 61: 32:on Knowledge's 29: 12: 11: 5: 567: 565: 557: 556: 551: 546: 541: 531: 530: 509: 508: 498: 495: 494: 493: 449: 448: 418: 417: 416: 415: 414: 413: 378: 377: 343: 340: 339: 338: 323: 322: 321: 298: 297: 258: 255: 249: 246: 243: 242: 239: 238: 235: 234: 227: 221: 220: 218: 201:the discussion 179: 167: 166: 161: 149: 148: 145: 144: 133: 127: 126: 124: 107:the discussion 94: 93: 77: 65: 64: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 566: 555: 552: 550: 547: 545: 542: 540: 537: 536: 534: 527: 526: 522: 518: 514: 507: 504: 503: 502: 496: 492: 488: 484: 480: 479: 478: 477: 473: 469: 466: 464: 458: 456: 447: 443: 439: 435: 434: 433: 432: 428: 424: 412: 408: 404: 400: 399: 398: 394: 390: 386: 382: 381: 380: 379: 376: 372: 368: 364: 363: 362: 361: 357: 353: 348: 341: 337: 333: 329: 324: 320: 316: 312: 307: 302: 301: 300: 299: 295: 291: 290: 289: 288: 284: 280: 274: 273: 269: 265: 256: 254: 247: 232: 226: 223: 222: 219: 202: 198: 194: 190: 186: 185: 180: 177: 173: 172: 168: 165: 162: 159: 155: 142: 138: 132: 129: 128: 125: 108: 104: 100: 99: 91: 85: 80: 78: 75: 71: 70: 66: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 510: 500: 462: 460: 454: 452: 450: 419: 384: 349: 345: 305: 275: 260: 251: 195:, and other 182: 137:Mid-priority 136: 96: 62:Mid‑priority 40:WikiProjects 483:Steelpillow 438:Steelpillow 389:Steelpillow 311:Steelpillow 248:Old comment 112:Mathematics 103:mathematics 59:Mathematics 533:Categories 465:} has 3... 457:} has 3... 306:extending 206:Polyhedra 197:polytopes 193:polyhedra 164:Polyhedra 403:Tom Ruen 367:Tom Ruen 328:Tom Ruen 279:Tom Ruen 264:Tom Ruen 189:polygons 350:Thanks 139:on the 30:C-class 468:Jumpow 36:scale. 521:talk 487:Talk 472:talk 442:Talk 427:talk 423:WesT 407:talk 393:Talk 371:talk 356:talk 352:WesT 332:talk 315:Talk 283:talk 268:talk 515:. — 225:??? 131:Mid 535:: 523:) 489:) 474:) 444:) 429:) 409:) 395:) 373:) 358:) 334:) 317:) 285:) 270:) 191:, 519:( 485:( 470:( 463:9 455:3 440:( 425:( 405:( 391:( 369:( 354:( 330:( 313:( 281:( 266:( 233:. 143:. 42::

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Tom Ruen
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22:31, 5 February 2015 (UTC)
Tom Ruen
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22:57, 5 February 2015 (UTC)

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