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Wythoff symbol

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The generator point can either be on or off each mirror, activated or not. This distinction creates 8 (2) possible forms, but the one where the generator point is on all the mirrors is impossible. The symbol that would normally refer to that is reused for the snub tilings.
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A Wythoff symbol consists of three numbers and a vertical bar. It represents one uniform polyhedron or tiling, although the same tiling/polyhedron can have different Wythoff symbols from different symmetry generators. For example, the regular
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Example Wythoff construction triangles with the 7 generator points. Lines to the active mirrors are colored red, yellow, and blue with the 3 nodes opposite them as associated by the Wythoff symbol.
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With a slight extension, Wythoff's symbol can be applied to all uniform polyhedra. However, the construction methods do not lead to all uniform tilings in Euclidean or hyperbolic space.
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on a fundamental triangle. This point must be chosen at equal distance from all edges that it does not lie on, and a perpendicular line is then dropped from it to each such edge.
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which is designated for the case where all mirrors are active, but odd-numbered reflected images are ignored. The resulting figure has rotational symmetry only.
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was developed to mark uniform polytopes and honeycombs in n-dimensional space within a fundamental simplex.
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The fundamental triangles are drawn in alternating colors as mirror images. The sequence of triangles (
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In this notation the mirrors are labeled by the reflection-order of the opposite vertex. The
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Greg Egan's applet to display uniform polyhedra using Wythoff's construction method
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respectively. The triangle is also represented with the same numbers, written (
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The eight forms for the Wythoff constructions from a general triangle (
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Example spherical, euclidean and hyperbolic tilings on right triangles
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Lists of uniform tilings on the sphere, plane, and hyperbolic plane
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indicates that the generator lies in the interior of the triangle.
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The Wythoff symbol is functionally similar to the more general
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A Shadertoy renderization of Wythoff's construction method
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indicates that the generator lies on the edge between
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Hyperbolic tilings are shown as a 95:, as well as 2 2 2 | with 3 colors and D 26: 18: 117:The three numbers in Wythoff's symbol, 1750: 1738: 1695: 1637:The Beauty of Geometry: Twelve Essays 1588:Uniform tilings in hyperbolic plane 75:can be represented by 3 | 2 4 with 13: 14: 1774: 1741:"Hyperbolic Planar Tessellations" 1688: 1552: 1539: 1526: 1513: 1500: 1489: 1476: 1463: 1454: 1439: 1426: 1413: 1400: 1387: 1374: 1361: 1348: 1339: 1324: 1311: 1298: 1285: 1272: 1259: 1246: 1233: 1224: 1209: 1196: 1183: 1170: 1157: 1144: 1131: 1118: 1109: 1094: 1081: 1068: 1055: 1042: 1029: 1016: 1003: 994: 979: 966: 953: 940: 927: 914: 901: 888: 879: 864: 851: 838: 825: 812: 799: 786: 773: 764: 654: 649: 644: 639: 634: 625: 620: 615: 610: 605: 596: 591: 586: 581: 576: 567: 562: 557: 552: 547: 538: 533: 528: 523: 518: 509: 504: 499: 494: 489: 480: 475: 470: 465: 460: 451: 446: 441: 436: 431: 1672:. Cambridge University Press. 105: 1: 1608: 47:is a notation representing a 1639:, Dover Publications, 1999, 319:3 2) change from spherical ( 283:A special use is the symbol 7: 1653:, Longuet-Higgins, Miller, 1566: 10: 1779: 323:= 3, 4, 5), to Euclidean ( 83:, and 2 4 | 2 as a square 1763:Polytope notation systems 1593:List of uniform polyhedra 756: 55:or plane tiling within a 16:Notation for tesselations 1583:List of uniform tilings 59:. It was first used by 305:Coxeter-Dynkin diagram 36: 24: 327:= 6), to hyperbolic ( 30: 22: 1661:1954, 246 A, 401–50. 49:Wythoff construction 1714:The Wythoff symbol 1697:Weisstein, Eric W. 1578:Regular polyhedron 276:values are listed 87:with 2 colors and 53:uniform polyhedron 37: 25: 1670:Polyhedron Models 1666:Wenninger, Magnus 1655:Uniform polyhedra 1619:Regular Polytopes 1564: 1563: 757:7 forms and snub 1770: 1744: 1710: 1709: 1700:"Wythoff symbol" 1683: 1573:Regular polytope 1556: 1543: 1530: 1517: 1504: 1493: 1480: 1467: 1458: 1443: 1430: 1417: 1404: 1391: 1378: 1365: 1352: 1343: 1328: 1315: 1302: 1289: 1276: 1263: 1250: 1237: 1228: 1213: 1200: 1187: 1174: 1161: 1148: 1135: 1122: 1113: 1098: 1085: 1072: 1059: 1046: 1033: 1020: 1007: 998: 983: 970: 957: 944: 931: 918: 905: 892: 883: 868: 855: 842: 829: 816: 803: 790: 777: 768: 754:Fund. triangles 659: 658: 657: 653: 652: 648: 647: 643: 642: 638: 637: 630: 629: 628: 624: 623: 619: 618: 614: 613: 609: 608: 601: 600: 599: 595: 594: 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Trans. 1658: 1654: 1636: 1617: 1550:| ∞ 3 2 1537:∞ 3 2 | 1524:∞ 3 | 2 1511:∞ | 3 2 1498:2 ∞ | 3 1487:2 | ∞ 3 1474:2 3 | ∞ 1461:3 | ∞ 2 1437:| 8 3 2 1424:8 3 2 | 1411:8 3 | 2 1398:8 | 3 2 1385:2 8 | 3 1372:2 | 8 3 1359:2 3 | 8 1346:3 | 8 2 1322:| 7 3 2 1309:7 3 2 | 1296:7 3 | 2 1283:7 | 3 2 1270:2 7 | 3 1257:2 | 7 3 1244:2 3 | 7 1231:3 | 7 2 1207:| 6 3 2 1194:6 3 2 | 1181:6 3 | 2 1168:6 | 3 2 1155:2 6 | 3 1142:2 | 6 3 1129:2 3 | 6 1116:3 | 6 2 1092:| 5 3 2 1079:5 3 2 | 1066:5 3 | 2 1053:5 | 3 2 1040:2 5 | 3 1027:2 | 5 3 1014:2 3 | 5 1001:3 | 5 2 977:| 4 3 2 964:4 3 2 | 951:4 3 | 2 938:4 | 3 2 925:2 4 | 3 912:2 | 4 3 899:2 3 | 4 886:3 | 4 2 862:| 3 3 2 849:3 3 2 | 836:3 3 | 2 823:3 | 3 2 810:2 3 | 3 797:2 | 3 3 784:2 3 | 3 771:3 | 3 2 747: 743: 737: 733: 726: 722: 717: 712: 708: 704: 699: 695: 691: 687: 682: 678: 674: 669: 417: 414: 407: 404: 398: 395: 389: 385: 380: 376: 370: 367: 361: 357: 350: 346: 335:projection. 328: 324: 320: 316: 314: 302: 298: 292: 289: 286: 282: 277: 273: 269: 265: 263: 255: 252: 249: 242: 238: 233: 229: 226: 219: 214: 211: 207: 199: 196: 193: 182: 162: 142: 126: 122: 118: 116: 111: 109: 101: 69: 44: 38: 32: 106:Description 1752:Categories 1609:References 99:symmetry. 1758:Polyhedra 1705:MathWorld 1559:3.3.3.3.∞ 1446:3.3.3.3.8 1331:3.3.3.3.7 1216:3.3.3.3.6 1101:3.3.3.3.5 986:3.3.3.3.4 871:3.3.3.3.3 410:2 | 401:| 2 366:2 | 1668:(1974). 1567:See also 1495:3.∞.3.∞ 93:symmetry 81:symmetry 41:geometry 1651:Coxeter 1634:Coxeter 1615:Coxeter 1533:3.4.∞.4 1452:(∞ 3 2) 1420:3.4.8.4 1381:3.8.3.8 1368:3.16.16 1337:(8 3 2) 1305:3.4.7.4 1266:3.7.3.7 1253:3.14.14 1222:(7 3 2) 1190:3.4.6.4 1151:3.6.3.6 1138:3.12.12 1107:(6 3 2) 1075:3.4.5.4 1036:3.5.3.5 1023:3.10.10 992:(5 3 2) 960:3.4.4.4 921:3.4.3.4 877:(4 3 2) 845:3.4.3.4 806:3.3.3.3 762:(3 3 2) 413:| 388:| 379:| 360:| 349:| 190:radians 187:⁠ 171:⁠ 167:⁠ 151:⁠ 147:⁠ 131:⁠ 61:Coxeter 1676:  1643:  1626:  1433:4.6.16 1318:4.6.14 1203:4.6.12 1088:4.6.10 278:before 169:, and 125:, and 43:, the 1546:4.6.∞ 1507:∞.6.6 1483:3.∞.∞ 1394:8.6.6 1279:7.6.6 1164:6.6.6 1049:5.6.6 973:4.6.8 934:4.6.6 908:3.8.8 858:4.6.6 819:3.6.6 793:3.6.6 85:prism 51:of a 33:p q r 1674:ISBN 1641:ISBN 1624:ISBN 742:3.3. 241:and 73:cube 746:.3. 732:4.2 729:.4 725:.4. 39:In 1754:: 1702:. 1657:, 736:.2 711:.2 707:.2 681:.2 677:.2 420:2 392:2 375:2 356:2 353:2 285:| 272:, 268:, 232:| 210:| 149:, 121:, 97:2h 91:4h 35:). 1743:. 1708:. 1682:. 1520:3 1470:∞ 1407:3 1355:8 1292:3 1240:7 1177:3 1125:6 1062:3 1010:5 947:3 895:4 832:3 780:3 748:q 744:p 738:q 734:p 727:q 723:p 718:q 713:q 709:q 705:p 700:q 698:. 696:p 694:. 692:q 690:. 688:p 683:p 679:p 675:q 670:p 418:q 415:p 408:q 405:p 399:q 396:p 390:q 386:p 381:q 377:p 371:q 368:p 362:p 358:q 351:p 347:q 329:p 325:p 321:p 317:p 293:r 290:q 287:p 274:r 270:q 266:p 258:| 256:r 253:q 250:p 245:, 243:q 239:p 234:r 230:q 227:p 222:, 220:p 215:r 212:q 208:p 200:r 197:q 194:p 183:r 179:/ 175:π 163:q 159:/ 155:π 143:p 139:/ 135:π 127:r 123:q 119:p 89:D 79:h 77:O

Index



geometry
Wythoff construction
uniform polyhedron
Schwarz triangle
Coxeter
Coxeter diagram
cube
Oh symmetry
prism
D4h symmetry
radians
Coxeter-Dynkin diagram
Poincaré disk
Wythoff symbol
Coxeter diagram
Vertex figure


3

3.6.6

3.3.3.3

3.6.6

3

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