Knowledge (XXG)

Talk:Complete graph

Source 📝

95: 85: 64: 31: 22: 1210:, even setting aside the questions of relevance (why a complete digraph + loops between trigrams rather than a complete bipartite graph between lower and upper sets of trigrams, or a complete system of combinations of elements rather than a graph, or a Boolean algebra, or...) and of whether there is sufficient significance to either topic. — 461:
how many subgraphs are there (where I would like to differentiate between subgraphs that are NOT isomophic to one another - clearly it is simple to enumerate all the subgraphs, calculate their adjacency matrices and get a computer program to get rid of all of the similar matrices so that you are left
173:
In the current version, the sentence "(..) a complete graph can be the worst case for large connected systems like social and computer networks" is POV. It needs explanation. Otherwise the statement is not generally true and needs to be removed. Why should a complete social network be any bad? Worse
682:, it states "The complete graph K4 is planar" and links to this article. Then, here, we have a drawing of K4 which makes it look non-planar (i.e. two of the edges cross in the drawing). This is bound to be confusing to people. I think it would make sense to either use the drawing of K4 from 1243:"complete" for digraphs, the graph with 4 edges (2 of them being of xy-type and 2 being yx-type) between each pair of vertices (x,y), would also be a complete digraph to those people who allow directed graphs to have such multiple arcs. So in this sense, the definition should be that there's 1242:
article says that "some authors consider a broader definition that allows directed graphs to have such multiple arcs", in which case there could be four edges between (x,y), for example two of them corresponding to xy and two of them corresponding to yx. According to the above definition of
1238:". Couldn't you have just added the citation and not complained about how "basic and obvious" it was and not mention me? The reference that you added says that a digraph is "complete" if for every pair vertices (x,y), the edges xy and yx both exist. But the 1262:
Unless otherwise specified, usually only one edge would be allowed in each direction in a digraph. I don't remember ever seeing a definition of complete graphs (without additional qualification in the name) that allowed the edge multiplicities to vary.
402:
It's completely inappropriate and I'm going to remove it. Even at the highest resolution it is hard to see the edges but only the interference pattern they make. It will only confuse people who come to this page for information on complete graphs.
1159:
of trigrams with the lower considered first, the upper second. Since there is a hexagram for every pair of bagua, in both orders, there is a directed edge in each direction for each pair of trigrams. Eight
792: 177:
I guess the person who wrote it was thinking of benefit-cost-ratio. But that needs some elaboration and possibly sources to make it credible. Otherwise not worthy of an existence in an encyclopedia.
151: 1307: 1033: 976: 638:
As I understand, the term "complete graph" means the same as "full mesh" in computer science (especially networking). Does anyone object to mentioning this fact in this article? --
904: 374:
yes, it is, but it adds little to the article. More like "ooh, look what my computer can do". I suppose it might illustrate that the number of connections increases rapidly
832: 1297: 1105: 337: 1072: 35: 1312: 1236:
supply requested notation for basic and obvious notation for which User:Dr. Universe could easily have run a search instead of making busywork for other editors
1292: 1322: 686:, or at least have a note on the drawing here pointing out that there is an alternate way to draw the graph which makes its planarity more apparent. -- 657:
Every German source I have seen says that the K is in honour of Kuratowski. "Complete graph" is "vollständiger Graph" in German, not "kompletter Graph".
141: 117: 614: 346: 1302: 1206:
So you're trying to use content you yourself wrote on another open Wiki (Wikibooks) as a reference for content here? It is very obviously not a
1317: 618: 350: 1164:
are included in the directed graph since there is a hexagram for each doubled trigram. The 56 edges and 8 loops are labeled 1 to 64 in a
108: 69: 979: 908: 840: 439:
Silly point - but this wiki could also define the concept for directional graphs. This request is motivated by the next two entries.
390: 1037: 726: 485:
Same as above request, but everything is to do with directed graphs (so their should be more subgraphs up to isomorphism...).
219:. The triangle has nothing but its sides and corners, but the octagon looks very complicated. Can anyone see how complicated an 1287: 44: 611: 343: 1107:, which is still connected. In this context, removing a vertex means also removing all edges incident to that vertex. — 1010:
They are maximally connected as the only vertex cut which disconnects the graph is the complete set of vertices.
1268: 1215: 1112: 50: 553:
Any graph, no matter how many vertices, can be embedded without crossings in 3d, for instance by placing the
282:
has 10 × (10 - 1) / 2 = 45. So yeah, they can look quite complicated!  :-) I guess since we've already got
1234:
I appreciate you adding the citation, but I don't understand why you had to attack me in the edit summary: "
983: 912: 844: 608: 486: 465: 386: 340: 378: 1252: 182: 928: 925:
And of course, you can also find the number through summation, though that may actually be more verbose:
700: 664: 228: 116:
on Knowledge (XXG). If you would like to participate, please visit the project page, where you can join
382: 94: 836: 862: 660: 21: 1264: 1231: 1211: 1161: 1108: 570: 196:(as in worst-case analysis) for such a network; which is of course not expressing a point of view. 798: 708: 690: 454:
Yes, this is a simple exercise, and I will probably hunt it down on the internet. But, say, for
100: 192:
Er, although this statement is poorly-written, I think this just means that it's the worst-case
84: 63: 1248: 1196: 1188: 1173: 1172:(Earth ☷, Water ☵, Air ☰, and Fire ☲.), the oppositely directed edges are consecutive.<ref 1169: 855: 723:
Not sure if there is any reason to mention it in the article or to add it to the infobox, but
643: 178: 1247:
edge going in each direction right? I wasn't sure about this so I wanted to see a reference.
1077: 462:
with ONLY isomorphically distinct subgraphs - but, surely, this has been done already?).
339:. I'm too lazy to create higher ones (pity as we need them for simplex Petrie polygons...) 315: 1050: 1207: 1239: 1144: 420:
I agree, thanks. I was going to remove it myself, and I am glad you did it first. --
1281: 704: 687: 197: 1192: 1184: 1168:, but the sequence is obscure. In the case of a pair of trigrams corresponding to 1165: 1156: 683: 679: 639: 522: 421: 474:
Is there a general way of determining all of the directed subgraphs of a directed
518: 514: 113: 404: 90: 587: 539: 500: 365: 304: 1148: 220: 212: 1272: 1256: 1219: 1200: 1152: 1116: 1041: 987: 916: 848: 712: 693: 668: 647: 621: 590: 573: 542: 535: 525: 510: 503: 489: 468: 424: 407: 368: 353: 224: 216: 200: 186: 1140: 499:
I have yet to see one but I think it would be very interesting. -
719:
Alternative formula for the number of edges in a complete graph
443:
Is there a general way of determining all of the subgraphs of
15: 787:{\displaystyle \textstyle {\frac {n(n-1)}{2}}={n \choose 2}} 1183:
mentioned in lede. Very old topic. Supports article well.
211:
This article has pictures of all regular polygons from a
1235: 513:
family has vertex/edge sets as complete graphs, so the
730: 1308:
Knowledge (XXG) level-5 vital articles in Mathematics
1080: 1053: 931: 865: 801: 729: 318: 112:, a collaborative effort to improve the coverage of 1015:(Where the word "they" refers to complete graphs.) 1099: 1066: 970: 898: 826: 786: 538:mention complete graphs as being 3D equivalents? - 331: 890: 869: 818: 805: 296:, we might as well add 9 and 10; or we could add 1191:) 04:20, 17 February 2022 (UTC) Provide WB link 1047:No, it doesn't. If you remove two vertices from 435:Extending this wiki to include complete digraphs 1029:(Because they are the endpoints of some edge.) 1024:removing any two vertices disconnects the graph 303:just to illustrate how messy they can get... -- 1298:Knowledge (XXG) vital articles in Mathematics 777: 764: 8: 249:? As a general rule, the complete graph on 607:Yes, but I was too lazy to make a graphic. 58: 1085: 1079: 1058: 1052: 947: 936: 930: 889: 868: 866: 864: 817: 804: 802: 800: 776: 763: 761: 731: 728: 323: 317: 701:separate article for "Tetrahedral graph" 586:OK, but is there a 12-vertex version? - 126:Knowledge (XXG):WikiProject Mathematics 60: 19: 1293:Knowledge (XXG) level-5 vital articles 1018:But if n ≥ 3, for the complete graph K 1313:B-Class vital articles in Mathematics 7: 1143:or trigrams form the verticies of a 1135:I Ching as complete digraph on bagua 1034:2601:200:C000:1A0:87C:FF45:2757:A6C9 1032:Or am I misunderstanding something? 971:{\displaystyle \sum _{i=1}^{n}(i-1)} 839:), and the latter is more succinct. 674:K4 example makes it look non-planar. 275:has 9 × (9 - 1) / 2 = 36 edges, and 106:This article is within the scope of 364:K100 added! It's really beautiful. 49:It is of interest to the following 873: 809: 768: 14: 1323:Mid-priority mathematics articles 703:; that could be the way to go... 129:Template:WikiProject Mathematics 93: 83: 62: 29: 20: 899:{\displaystyle {n+1 \choose 2}} 146:This article has been rated as 1303:B-Class level-5 vital articles 1273:04:04, 10 September 2022 (UTC) 1257:01:46, 10 September 2022 (UTC) 965: 953: 854:It's similar to a formula for 749: 737: 557:th vertex at the coordinates ( 1: 1220:06:32, 17 February 2022 (UTC) 1201:04:34, 17 February 2022 (UTC) 827:{\displaystyle {n \choose 2}} 713:15:23, 12 November 2012 (UTC) 699:French Knowledge (XXG) has a 648:05:04, 3 September 2008 (UTC) 622:11:13, 9 September 2009 (UTC) 425:03:37, 30 December 2006 (UTC) 408:01:56, 30 December 2006 (UTC) 354:11:12, 9 September 2009 (UTC) 120:and see a list of open tasks. 1318:B-Class mathematics articles 988:10:04, 5 February 2018 (UTC) 917:09:40, 5 February 2018 (UTC) 849:12:52, 3 February 2018 (UTC) 369:18:41, 30 October 2006 (UTC) 1127:The following example of a 1117:17:41, 3 January 2022 (UTC) 1042:17:36, 3 January 2022 (UTC) 1339: 591:15:41, 6 August 2007 (UTC) 574:15:13, 6 August 2007 (UTC) 543:15:41, 6 August 2007 (UTC) 534:Interesting. So shouldn't 526:14:15, 6 August 2007 (UTC) 504:06:56, 6 August 2007 (UTC) 201:21:30, 28 April 2008 (UTC) 187:21:27, 28 April 2008 (UTC) 669:15:17, 1 March 2010 (UTC) 231:01:21, 16 Oct 2004 (UTC) 145: 78: 57: 1004:contains this sentence: 490:19:01, 30 May 2007 (UTC) 469:19:01, 30 May 2007 (UTC) 307:02:22, 18 Oct 2004 (UTC) 152:project's priority scale 1100:{\displaystyle K_{n-2}} 694:17:58, 1 May 2012 (UTC) 174:in comparison to what? 109:WikiProject Mathematics 1288:B-Class vital articles 1101: 1068: 972: 952: 900: 828: 788: 333: 332:{\displaystyle K_{11}} 1174:b:I Ching/Octal Bagua 1102: 1069: 1067:{\displaystyle K_{n}} 973: 932: 901: 829: 789: 653:Origin of the K in Kn 334: 43:on Knowledge (XXG)'s 36:level-5 vital article 1155:. The hexagrams are 1078: 1051: 929: 863: 837:binomial coefficient 799: 727: 316: 207:Enneagon and Decagon 132:mathematics articles 268:- 1) / 2 edges; so 169:POV on "worst case" 1097: 1074:you are left with 1064: 968: 896: 856:triangular numbers 824: 784: 783: 495:3D complete graph? 487:ConcernedScientist 481:UP TO isomorphism? 466:ConcernedScientist 450:UP TO isomorphism? 329: 101:Mathematics portal 45:content assessment 1226:Complete digraphs 906: 888: 834: 816: 775: 756: 395: 381:comment added by 166: 165: 162: 161: 158: 157: 1330: 1181:Complete digraph 1129:complete digraph 1106: 1104: 1103: 1098: 1096: 1095: 1073: 1071: 1070: 1065: 1063: 1062: 996:Is this correct? 977: 975: 974: 969: 951: 946: 905: 903: 902: 897: 895: 894: 893: 884: 872: 859: 833: 831: 830: 825: 823: 822: 821: 808: 795: 793: 791: 790: 785: 782: 781: 780: 767: 757: 752: 732: 394: 375: 338: 336: 335: 330: 328: 327: 134: 133: 130: 127: 124: 103: 98: 97: 87: 80: 79: 74: 66: 59: 42: 33: 32: 25: 24: 16: 1338: 1337: 1333: 1332: 1331: 1329: 1328: 1327: 1278: 1277: 1228: 1208:reliable source 1137: 1125: 1081: 1076: 1075: 1054: 1049: 1048: 1021: 998: 927: 926: 874: 867: 861: 860: 803: 797: 796: 762: 733: 725: 724: 721: 676: 655: 636: 497: 483: 480: 460: 452: 449: 437: 376: 362: 319: 314: 313: 302: 295: 288: 281: 274: 259: 248: 241: 209: 171: 131: 128: 125: 122: 121: 99: 92: 72: 40: 30: 12: 11: 5: 1336: 1334: 1326: 1325: 1320: 1315: 1310: 1305: 1300: 1295: 1290: 1280: 1279: 1276: 1275: 1265:David Eppstein 1240:Directed graph 1232:David Eppstein 1227: 1224: 1223: 1222: 1212:David Eppstein 1170:Greek elements 1145:directed graph 1136: 1133: 1124: 1123:For the record 1121: 1120: 1119: 1109:David Eppstein 1094: 1091: 1088: 1084: 1061: 1057: 1019: 1007: 997: 994: 993: 992: 991: 990: 967: 964: 961: 958: 955: 950: 945: 942: 939: 935: 920: 919: 892: 887: 883: 880: 877: 871: 820: 815: 812: 807: 779: 774: 771: 766: 760: 755: 751: 748: 745: 742: 739: 736: 720: 717: 716: 715: 675: 672: 654: 651: 635: 632: 631: 630: 629: 628: 627: 626: 625: 624: 598: 597: 596: 595: 594: 593: 579: 578: 577: 576: 571:David Eppstein 548: 547: 546: 545: 529: 528: 496: 493: 482: 478: 472: 458: 451: 447: 441: 436: 433: 432: 431: 430: 429: 428: 427: 413: 412: 411: 410: 397: 396: 361: 358: 357: 356: 326: 322: 312:I added up to 309: 308: 300: 293: 286: 279: 272: 257: 246: 239: 208: 205: 204: 203: 170: 167: 164: 163: 160: 159: 156: 155: 144: 138: 137: 135: 118:the discussion 105: 104: 88: 76: 75: 67: 55: 54: 48: 26: 13: 10: 9: 6: 4: 3: 2: 1335: 1324: 1321: 1319: 1316: 1314: 1311: 1309: 1306: 1304: 1301: 1299: 1296: 1294: 1291: 1289: 1286: 1285: 1283: 1274: 1270: 1266: 1261: 1260: 1259: 1258: 1254: 1250: 1246: 1241: 1237: 1233: 1225: 1221: 1217: 1213: 1209: 1205: 1204: 1203: 1202: 1198: 1194: 1190: 1186: 1182: 1177: 1175: 1171: 1167: 1163: 1158: 1157:ordered pairs 1154: 1150: 1146: 1142: 1134: 1132: 1130: 1122: 1118: 1114: 1110: 1092: 1089: 1086: 1082: 1059: 1055: 1046: 1045: 1044: 1043: 1039: 1035: 1030: 1027: 1025: 1016: 1013: 1011: 1005: 1003: 995: 989: 985: 981: 980:77.126.47.196 962: 959: 956: 948: 943: 940: 937: 933: 924: 923: 922: 921: 918: 914: 910: 909:77.126.47.196 885: 881: 878: 875: 857: 853: 852: 851: 850: 846: 842: 841:77.126.47.196 838: 813: 810: 772: 769: 758: 753: 746: 743: 740: 734: 718: 714: 710: 706: 702: 698: 697: 696: 695: 692: 689: 685: 681: 673: 671: 670: 666: 662: 658: 652: 650: 649: 645: 641: 633: 623: 620: 616: 613: 610: 606: 605: 604: 603: 602: 601: 600: 599: 592: 589: 585: 584: 583: 582: 581: 580: 575: 572: 568: 564: 560: 556: 552: 551: 550: 549: 544: 541: 537: 533: 532: 531: 530: 527: 524: 520: 516: 512: 508: 507: 506: 505: 502: 494: 492: 491: 488: 477: 473: 471: 470: 467: 463: 457: 446: 442: 440: 434: 426: 423: 419: 418: 417: 416: 415: 414: 409: 406: 401: 400: 399: 398: 392: 388: 384: 380: 373: 372: 371: 370: 367: 359: 355: 352: 348: 345: 342: 324: 320: 311: 310: 306: 299: 292: 285: 278: 271: 267: 263: 256: 252: 245: 238: 234: 233: 232: 230: 229:66.245.86.215 226: 222: 218: 214: 206: 202: 199: 195: 191: 190: 189: 188: 184: 180: 175: 168: 153: 149: 143: 140: 139: 136: 119: 115: 111: 110: 102: 96: 91: 89: 86: 82: 81: 77: 71: 68: 65: 61: 56: 52: 46: 38: 37: 27: 23: 18: 17: 1249:Dr. Universe 1245:at least one 1244: 1229: 1180: 1178: 1166:lookup table 1138: 1131:was posted: 1128: 1126: 1031: 1028: 1023: 1017: 1014: 1009: 1006: 1001: 1000:The section 999: 722: 684:Planar graph 680:Planar graph 677: 659: 656: 637: 566: 562: 558: 554: 498: 484: 475: 464: 455: 453: 444: 438: 383:24.18.43.240 363: 297: 290: 283: 276: 269: 265: 261: 254: 250: 243: 236: 227:will look?? 210: 193: 179:Tang Wenlong 176: 172: 148:Mid-priority 147: 107: 73:Mid‑priority 51:WikiProjects 34: 519:pentachoron 517:is 3D, and 515:tetrahedron 377:—Preceding 123:Mathematics 114:mathematics 70:Mathematics 1282:Categories 1179:Reverted! 1139:The eight 1002:Properties 253:vertices, 1176:/ref: --> 1149:hexagrams 1147:given by 661:Pluslucis 634:Full mesh 609:Professor 341:Professor 235:You mean 39:is rated 705:AnonMoos 688:RoySmith 615:Fiendish 523:Tom Ruen 391:contribs 379:unsigned 347:Fiendish 221:enneagon 213:triangle 198:Dcoetzee 1193:Rgdboer 1185:Rgdboer 1153:I Ching 1151:in the 794:(where 640:chrylis 536:simplex 521:is 4D. 511:simplex 422:Dominus 225:decagon 217:octagon 150:on the 41:B-class 691:(talk) 260:, has 215:to an 47:scale. 1162:loops 1141:bagua 835:is a 405:McKay 28:This 1269:talk 1253:talk 1216:talk 1197:talk 1189:talk 1113:talk 1038:talk 984:talk 913:talk 845:talk 709:talk 665:talk 644:talk 619:Esq. 588:Eeky 569:). — 540:Eeky 509:The 501:Eeky 387:talk 366:Alpt 360:K100 351:Esq. 305:Ejrh 242:and 194:size 183:talk 858:: 678:In 301:100 289:to 264:× ( 223:or 142:Mid 1284:: 1271:) 1255:) 1218:) 1199:) 1115:) 1090:− 1040:) 1026:. 1022:, 1012:" 986:) 978:. 960:− 934:∑ 915:) 907:. 847:) 744:− 711:) 667:) 646:) 617:, 612:M. 565:, 403:-- 393:) 389:• 349:, 344:M. 325:11 280:10 247:10 185:) 1267:( 1263:— 1251:( 1230:@ 1214:( 1195:( 1187:( 1111:( 1093:2 1087:n 1083:K 1060:n 1056:K 1036:( 1020:n 1008:" 982:( 966:) 963:1 957:i 954:( 949:n 944:1 941:= 938:i 911:( 891:) 886:2 882:1 879:+ 876:n 870:( 843:( 819:) 814:2 811:n 806:( 778:) 773:2 770:n 765:( 759:= 754:2 750:) 747:1 741:n 738:( 735:n 707:( 663:( 642:( 567:i 563:i 561:, 559:i 555:i 479:j 476:K 459:4 456:K 448:j 445:K 385:( 321:K 298:K 294:8 291:K 287:1 284:K 277:K 273:9 270:K 266:n 262:n 258:n 255:K 251:n 244:K 240:9 237:K 181:( 154:. 53::

Index


level-5 vital article
content assessment
WikiProjects
WikiProject icon
Mathematics
WikiProject icon
icon
Mathematics portal
WikiProject Mathematics
mathematics
the discussion
Mid
project's priority scale
Tang Wenlong
talk
21:27, 28 April 2008 (UTC)
Dcoetzee
21:30, 28 April 2008 (UTC)
triangle
octagon
enneagon
decagon
66.245.86.215
Ejrh
Professor
M.
Fiendish
Esq.
11:12, 9 September 2009 (UTC)

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.