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Ordered graph

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Given an ordered graph, its induced graph is another ordered graph obtained by joining some pairs of nodes that are both parents of another node. In particular, nodes are considered in turn according to the ordering, from last to first. For each node, if two of its parents are not joined by an edge,
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Processing nodes in order matters, as the introduced edges may create new parents, which are then relevant to the introduction of new edges. The following example shows that a different ordering produces a different induced graph of the same original graph. The ordering is the same as above but
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As an example, the induced graph of an ordered graph is calculated. The ordering is represented by the position of its nodes in the figures: a is the last node and d is the first.
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has no parent as well, the final induced graph is the one above. This induced graph differs from the one produced by the previous ordering.
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In an ordered graph, the parents of a node are the nodes that are adjacent to it and precede it in the ordering. More precisely,
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is added to the graph. Since the parents of a node are always connected with each other, the induced graph is always
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of an ordered graph is obtained by adding some edges to an ordering graph, using the method outlined below. The
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are not joined this time. As a result, no new edge is introduced. Since
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in the ordering. Since they are not joined by an edge, one is added.
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does not produce any change, as this node has no parents.
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as a parent in the partially built induced graph. Indeed,
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are parents of it and are not joined by an edge, the edge
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that edge is added. In other words, when considering node
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of an ordered graph is the width of its induced graph.
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As a result, an edge joining 8: 161: 143: 1036: 1016: 996: 976: 956: 936: 916: 896: 876: 856: 831: 808: 788: 746: 726: 702: 679: 659: 639: 619: 599: 579: 559: 539: 516: 496: 476: 456: 436: 411: 389: 318: 298: 278: 258: 217: 179: 141: 121: 101: 69:Learn how and when to remove this message 1135:Extensions and generalizations of graphs 167:{\displaystyle \langle N,E,<\rangle } 32:This article includes a list of general 1097: 16:Graph with a total order over its nodes 406:Edge added considering the parents of 384:Edge added considering the parents of 451:is considered first. Its parents are 7: 38:it lacks sufficient corresponding 14: 931:. This node has only one parent ( 763: 354: 774: 767: 372: 365: 358: 23: 851:As in the previous case, both 332: 320: 193: 181: 1: 783:Same graph, but the order of 491:, as they are both joined to 1151: 205:{\displaystyle (n,m)\in E} 826:Graph after considering 53:more precise citations. 1130:Constraint programming 1078:Dechter, Rina (2003). 1045: 1025: 1005: 985: 965: 945: 925: 905: 885: 865: 840: 817: 797: 755: 735: 711: 688: 668: 648: 628: 608: 588: 568: 548: 525: 505: 485: 465: 445: 420: 398: 339: 307: 287: 267: 232: 231:{\displaystyle n<m} 206: 168: 130: 110: 1081:Constraint Processing 1046: 1026: 1006: 986: 971:. Its only parent is 966: 946: 926: 906: 886: 866: 841: 818: 798: 756: 736: 712: 689: 669: 649: 629: 609: 589: 569: 549: 526: 506: 486: 466: 446: 421: 399: 340: 338:{\displaystyle (m,l)} 308: 288: 268: 233: 207: 169: 136:in the ordered graph 131: 111: 1035: 1015: 995: 975: 955: 935: 915: 895: 875: 855: 830: 807: 787: 745: 725: 701: 678: 658: 638: 618: 598: 578: 558: 538: 515: 495: 475: 455: 435: 410: 388: 381:The original graph. 317: 297: 277: 257: 216: 178: 140: 120: 100: 1084:. Morgan Kaufmann. 1041: 1021: 1001: 981: 961: 941: 921: 901: 881: 861: 836: 813: 793: 751: 731: 707: 684: 664: 644: 624: 604: 584: 564: 544: 521: 501: 481: 461: 441: 416: 394: 335: 303: 283: 263: 228: 202: 164: 126: 106: 1066:Local consistency 1044:{\displaystyle d} 1024:{\displaystyle c} 1004:{\displaystyle b} 984:{\displaystyle d} 964:{\displaystyle b} 944:{\displaystyle b} 924:{\displaystyle c} 904:{\displaystyle a} 884:{\displaystyle c} 864:{\displaystyle b} 849: 848: 839:{\displaystyle a} 816:{\displaystyle c} 796:{\displaystyle b} 754:{\displaystyle c} 734:{\displaystyle b} 710:{\displaystyle d} 687:{\displaystyle d} 667:{\displaystyle c} 647:{\displaystyle b} 634:and also precede 627:{\displaystyle b} 607:{\displaystyle c} 587:{\displaystyle c} 567:{\displaystyle d} 547:{\displaystyle b} 524:{\displaystyle a} 511:and both precede 504:{\displaystyle a} 484:{\displaystyle c} 464:{\displaystyle b} 444:{\displaystyle a} 429: 428: 419:{\displaystyle b} 397:{\displaystyle a} 306:{\displaystyle l} 286:{\displaystyle m} 266:{\displaystyle n} 129:{\displaystyle m} 109:{\displaystyle n} 79: 78: 71: 1142: 1114: 1111: 1105: 1102: 1085: 1050: 1048: 1047: 1042: 1030: 1028: 1027: 1022: 1010: 1008: 1007: 1002: 990: 988: 987: 982: 970: 968: 967: 962: 950: 948: 947: 942: 930: 928: 927: 922: 910: 908: 907: 902: 890: 888: 887: 882: 870: 868: 867: 862: 845: 843: 842: 837: 822: 820: 819: 814: 802: 800: 799: 794: 778: 771: 764: 760: 758: 757: 752: 740: 738: 737: 732: 716: 714: 713: 708: 693: 691: 690: 685: 673: 671: 670: 665: 653: 651: 650: 645: 633: 631: 630: 625: 613: 611: 610: 605: 593: 591: 590: 585: 573: 571: 570: 565: 553: 551: 550: 545: 530: 528: 527: 522: 510: 508: 507: 502: 490: 488: 487: 482: 470: 468: 467: 462: 450: 448: 447: 442: 425: 423: 422: 417: 403: 401: 400: 395: 376: 369: 362: 355: 344: 342: 341: 336: 312: 310: 309: 304: 292: 290: 289: 284: 272: 270: 269: 264: 237: 235: 234: 229: 211: 209: 208: 203: 173: 171: 170: 165: 135: 133: 132: 127: 115: 113: 112: 107: 93:over its nodes. 74: 67: 63: 60: 54: 49:this article by 40:inline citations 27: 26: 19: 1150: 1149: 1145: 1144: 1143: 1141: 1140: 1139: 1120: 1119: 1118: 1117: 1112: 1108: 1103: 1099: 1077: 1074: 1057: 1033: 1032: 1013: 1012: 993: 992: 973: 972: 953: 952: 933: 932: 913: 912: 893: 892: 891:are parents of 873: 872: 853: 852: 828: 827: 805: 804: 785: 784: 743: 742: 723: 722: 699: 698: 676: 675: 656: 655: 636: 635: 616: 615: 596: 595: 576: 575: 556: 555: 536: 535: 513: 512: 493: 492: 473: 472: 453: 452: 433: 432: 408: 407: 386: 385: 315: 314: 295: 294: 275: 274: 255: 254: 214: 213: 176: 175: 138: 137: 118: 117: 116:is a parent of 98: 97: 75: 64: 58: 55: 45:Please help to 44: 28: 24: 17: 12: 11: 5: 1148: 1146: 1138: 1137: 1132: 1122: 1121: 1116: 1115: 1106: 1096: 1095: 1094: 1093: 1073: 1070: 1069: 1068: 1063: 1061:Directed graph 1056: 1053: 1040: 1020: 1000: 980: 960: 940: 920: 900: 880: 860: 847: 846: 835: 824: 812: 792: 780: 779: 772: 750: 730: 706: 683: 663: 643: 623: 603: 583: 563: 543: 520: 500: 480: 460: 440: 427: 426: 415: 404: 393: 382: 378: 377: 370: 363: 334: 331: 328: 325: 322: 302: 282: 262: 227: 224: 221: 201: 198: 195: 192: 189: 186: 183: 163: 160: 157: 154: 151: 148: 145: 125: 105: 77: 76: 31: 29: 22: 15: 13: 10: 9: 6: 4: 3: 2: 1147: 1136: 1133: 1131: 1128: 1127: 1125: 1110: 1107: 1101: 1098: 1092: 1091:1-55860-890-7 1088: 1083: 1082: 1076: 1075: 1071: 1067: 1064: 1062: 1059: 1058: 1054: 1052: 1038: 1018: 998: 978: 958: 938: 918: 898: 878: 858: 833: 825: 810: 790: 782: 781: 777: 773: 770: 766: 765: 762: 761:are swapped. 748: 728: 718: 704: 695: 681: 661: 641: 621: 614:is joined to 601: 581: 561: 541: 532: 518: 498: 478: 458: 438: 413: 405: 391: 383: 380: 379: 375: 371: 368: 364: 361: 357: 356: 353: 350: 348: 329: 326: 323: 300: 280: 260: 250: 248: 247:induced width 244: 243:induced graph 239: 225: 222: 219: 199: 196: 190: 187: 184: 158: 155: 152: 149: 146: 123: 103: 94: 92: 88: 84: 83:ordered graph 73: 70: 62: 52: 48: 42: 41: 35: 30: 21: 20: 1109: 1100: 1080: 850: 719: 697:Considering 696: 533: 430: 351: 251: 246: 242: 240: 95: 82: 80: 65: 56: 37: 823:is swapped 91:total order 51:introducing 1124:Categories 1072:References 991:. Indeed, 694:is added. 273:, if both 59:March 2010 34:references 197:∈ 162:⟩ 144:⟨ 1055:See also 347:chordal 89:with a 47:improve 1089:  36:, but 534:Node 431:Node 87:graph 85:is a 1087:ISBN 1011:and 871:and 803:and 741:and 674:and 471:and 293:and 241:The 223:< 212:and 159:< 174:if 81:An 1126:: 349:. 1039:d 1019:c 999:b 979:d 959:b 939:b 919:c 899:a 879:c 859:b 834:a 811:c 791:b 749:c 729:b 705:d 682:d 662:c 642:b 622:b 602:c 582:c 562:d 542:b 519:a 499:a 479:c 459:b 439:a 414:b 392:a 333:) 330:l 327:, 324:m 321:( 301:l 281:m 261:n 226:m 220:n 200:E 194:) 191:m 188:, 185:n 182:( 156:, 153:E 150:, 147:N 124:m 104:n 72:) 66:( 61:) 57:( 43:.

Index

references
inline citations
improve
introducing
Learn how and when to remove this message
graph
total order
chordal





Directed graph
Local consistency
Constraint Processing
ISBN
1-55860-890-7
Categories
Constraint programming
Extensions and generalizations of graphs

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