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Relaxation (approximation)

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The first property states that the original problem's feasible domain is a subset of the relaxed problem's feasible domain. The second property states that the original problem's objective-function is greater than or equal to the relaxed problem's objective-function.
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Murty, Katta G. (1983). "16 Iterative methods for linear inequalities and linear programs (especially 16.2 Relaxation methods, and 16.4 Sparsity-preserving iterative SOR algorithms for linear programming)".
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of a complicated problem in combinatorial optimization penalizes violations of some constraints, allowing an easier relaxed problem to be solved. Relaxation techniques complement or supplement
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algorithms of combinatorial optimization; linear programming and Lagrangian relaxations are used to obtain bounds in branch-and-bound algorithms for integer programming.
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of a difficult problem by a nearby problem that is easier to solve. A solution of the relaxed problem provides information about the original problem.
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Relaxation methods for finding feasible solutions to linear inequality systems arise in linear programming and in Lagrangian relaxation.
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Geoffrion, A. M. (1971). "Duality in Nonlinear Programming: A Simplified Applications-Oriented Development".
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problem removes the integrality constraint and so allows non-integer rational solutions. A
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Goffin, J.-L. (1980). "The relaxation method for solving systems of linear inequalities".
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Semicontinuity, Relaxation and Integral Representation in the Calculus of Variations
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George L. Nemhauser and Laurence A. Wolsey, Integer programming (pp. 447–527);
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The modeling strategy of relaxation should not be confused with
168:{\displaystyle z=\min\{c(x):x\in X\subseteq \mathbf {R} ^{n}\}} 1088:
Relaxation in Optimization Theory and Variational Calculus
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is an optimal solution of the original problem, then
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L. T. Gubin, Boris T. Polyak, and E. V. Raik (1969)
977:Programmation mathĂ©matique: ThĂ©orie et algorithmes 702: 673: 619: 592: 552: 468: 422: 382: 356: 304: 265: 167: 201: 117: 952:Mathematical programming: Theory and algorithms 1052:, Polyhedral combinatorics (pp. 371–446); 8: 630:If in addition to the previous assumptions, 260: 204: 178:is another minimization problem of the form 162: 120: 777: 686: 641: 635: 611: 605: 584: 571: 565: 544: 528: 515: 499: 481: 469:{\displaystyle x^{*}\in X\subseteq X_{R}} 460: 441: 435: 414: 408: 369: 324: 318: 290: 284: 254: 249: 239: 211: 192: 186: 156: 151: 109: 773: 771: 769: 765: 750: 827: 815: 791: 803: 7: 1069:Optimization in operations research 997:. New York: John Wiley & Sons. 914:Mathematics of Operations Research 688: 25: 18:Relaxation technique (mathematics) 357:{\displaystyle c_{R}(x)\leq c(x)} 974:Translated by Steven Vajda from 305:{\displaystyle X_{R}\supseteq X} 250: 152: 703:{\displaystyle \forall x\in X} 668: 662: 653: 647: 593:{\displaystyle x^{*}\in X_{R}} 534: 521: 505: 492: 351: 345: 336: 330: 223: 217: 132: 126: 1: 1090:. Berlin: Walter de Gruyter. 830:, Section 4.3.7, pp. 120–123. 720:Linear programming relaxation 674:{\displaystyle c_{R}(x)=c(x)} 101:of the minimization problem 600:provides an upper bound on 1141: 1115:Relaxation (approximation) 1067:Rardin, Ronald L. (1998). 714:Some relaxation techniques 276:with these two properties 75:successive over-relaxation 1120:Mathematical optimization 29:mathematical optimization 730:Semidefinite relaxation 979:. Paris: Dunod. 1983. 704: 675: 621: 594: 554: 470: 424: 384: 383:{\displaystyle x\in X} 358: 306: 267: 169: 79:differential equations 39:. A relaxation is an 1086:RoubĂ­ÄŤek, T. (1997). 881:Buttazzo, G. (1989). 725:Lagrangian relaxation 705: 676: 622: 620:{\displaystyle z_{R}} 595: 555: 471: 425: 423:{\displaystyle x^{*}} 385: 359: 307: 268: 170: 56:Lagrangian relaxation 927:10.1287/moor.5.3.388 735:Surrogate relaxation 685: 634: 604: 564: 480: 434: 407: 368: 317: 283: 185: 108: 83:linear least-squares 31:and related fields, 950:Minoux, M. (1986). 806:, pp. 453–464. 52:integer programming 995:Linear programming 700: 671: 617: 590: 550: 466: 420: 380: 354: 302: 263: 165: 87:linear programming 48:linear programming 1097:978-3-11-014542-7 1078:978-0-02-398415-0 1071:. Prentice Hall. 1059:Claude LemarĂ©chal 1050:W. R. Pulleyblank 1034:978-0-444-87284-5 1004:978-0-471-09725-9 961:978-0-471-90170-9 67:iterative methods 50:relaxation of an 37:modeling strategy 16:(Redirected from 1132: 1101: 1082: 1046: 1021:Nemhauser, G. L. 1016: 988: 973: 946: 907: 886: 868: 865: 859: 856:Isaac Schoenberg 852:Theodore Motzkin 849: 843: 837: 831: 825: 819: 813: 807: 801: 795: 789: 780: 778:Geoffrion (1971) 775: 758: 755: 709: 707: 706: 701: 680: 678: 677: 672: 646: 645: 626: 624: 623: 618: 616: 615: 599: 597: 596: 591: 589: 588: 576: 575: 559: 557: 556: 551: 549: 548: 533: 532: 520: 519: 504: 503: 475: 473: 472: 467: 465: 464: 446: 445: 429: 427: 426: 421: 419: 418: 389: 387: 386: 381: 363: 361: 360: 355: 329: 328: 311: 309: 308: 303: 295: 294: 272: 270: 269: 264: 259: 258: 253: 244: 243: 216: 215: 197: 196: 174: 172: 171: 166: 161: 160: 155: 60:branch and bound 21: 1140: 1139: 1135: 1134: 1133: 1131: 1130: 1129: 1105: 1104: 1098: 1085: 1079: 1066: 1035: 1019: 1005: 991: 975: 962: 949: 910: 889: 880: 877: 872: 871: 866: 862: 850: 846: 838: 834: 826: 822: 814: 810: 802: 798: 790: 783: 776: 767: 762: 761: 756: 752: 747: 716: 683: 682: 637: 632: 631: 607: 602: 601: 580: 567: 562: 561: 540: 524: 511: 495: 478: 477: 456: 437: 432: 431: 410: 405: 404: 401: 366: 365: 320: 315: 314: 286: 281: 280: 248: 235: 207: 188: 183: 182: 150: 106: 105: 95: 46:For example, a 23: 22: 15: 12: 11: 5: 1138: 1136: 1128: 1127: 1125:Approximations 1122: 1117: 1107: 1106: 1103: 1102: 1096: 1083: 1077: 1064: 1063: 1062: 1056: 1053: 1033: 1017: 1003: 989: 960: 947: 921:(3): 388–414. 908: 887: 876: 873: 870: 869: 860: 844: 832: 820: 808: 796: 781: 764: 763: 760: 759: 749: 748: 746: 743: 742: 741: 732: 727: 722: 715: 712: 699: 696: 693: 690: 670: 667: 664: 661: 658: 655: 652: 649: 644: 640: 614: 610: 587: 583: 579: 574: 570: 547: 543: 539: 536: 531: 527: 523: 518: 514: 510: 507: 502: 498: 494: 491: 488: 485: 463: 459: 455: 452: 449: 444: 440: 417: 413: 400: 397: 392: 391: 379: 376: 373: 353: 350: 347: 344: 341: 338: 335: 332: 327: 323: 312: 301: 298: 293: 289: 274: 273: 262: 257: 252: 247: 242: 238: 234: 231: 228: 225: 222: 219: 214: 210: 206: 203: 200: 195: 191: 176: 175: 164: 159: 154: 149: 146: 143: 140: 137: 134: 131: 128: 125: 122: 119: 116: 113: 94: 91: 24: 14: 13: 10: 9: 6: 4: 3: 2: 1137: 1126: 1123: 1121: 1118: 1116: 1113: 1112: 1110: 1099: 1093: 1089: 1084: 1080: 1074: 1070: 1065: 1060: 1057: 1054: 1051: 1048: 1047: 1044: 1040: 1036: 1030: 1026: 1022: 1018: 1014: 1010: 1006: 1000: 996: 990: 986: 982: 978: 971: 967: 963: 957: 953: 948: 944: 940: 936: 932: 928: 924: 920: 916: 915: 909: 905: 901: 897: 893: 888: 884: 879: 878: 874: 864: 861: 857: 853: 848: 845: 841: 836: 833: 829: 828:Minoux (1986) 824: 821: 817: 816:Minoux (1986) 812: 809: 805: 800: 797: 793: 792:Goffin (1980) 788: 786: 782: 779: 774: 772: 770: 766: 754: 751: 744: 740: 736: 733: 731: 728: 726: 723: 721: 718: 717: 713: 711: 697: 694: 691: 665: 659: 656: 650: 642: 638: 628: 612: 608: 585: 581: 577: 572: 568: 560:. 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Index

Relaxation technique (mathematics)
mathematical optimization
modeling strategy
approximation
linear programming
integer programming
Lagrangian relaxation
branch and bound
iterative methods
relaxation
successive over-relaxation
differential equations
linear least-squares
linear programming
Linear programming relaxation
Lagrangian relaxation
Semidefinite relaxation
Surrogate relaxation
duality



Geoffrion (1971)


Goffin (1980)
Murty (1983)
Minoux (1986)
Minoux (1986)
Shmuel Agmon

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