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Big M method

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The simplex algorithm is the original and still one of the most widely used methods for solving linear maximization problems. However, to apply it, the origin (all variables equal to 0) must be a feasible point. This condition is satisfied only when all the constraints (except non-negativity) are
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When used in the constraints themselves, one of the many uses of Big M, for example, refers to ensuring equality of variables only when a certain binary variable takes on one value, but to leave the variables "open" if the binary variable takes on its opposite value. One instance of this is as
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less-than constraints and with positive constant on the right-hand side. The Big M method introduces surplus and artificial variables to convert all inequalities into that form. The "Big M" refers to a large number associated with the artificial variables, represented by the letter M.
78:. The Big M method extends the simplex algorithm to problems that contain "greater-than" constraints. It does so by associating the constraints with large negative constants which would not be part of any optimal solution, if it exists. 208:
When used in the objective function, the Big M method sometimes refers to formulations of linear optimization problems in which violations of a constraint or set of constraints are associated with a large positive penalty constant, M.
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For a sufficiently large M, the optimal solution contains any artificial variables in the basis (i.e. positive values) if and only if the problem is not feasible.
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However, the a-priori selection of an appropriate value for M is not trivial. A way to overcome the need to specify the value of M is described in.
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The value of M must be chosen sufficiently large so that the artificial variable would not be part of any feasible solution.
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Choose a large positive Value M and introduce a term in the objective of the form −M multiplying the artificial variables.
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If the problem is of minimization, transform to maximization by multiplying the objective by −1.
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A THREE-PHASE SIMPLEX METHOD FOR INFEASIBLE AND UNBOUNDED LINEAR PROGRAMMING PROBLEMS
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follows: for a sufficiently large M and z binary variable (0 or 1), the constraints
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Multiply the inequality constraints to ensure that the right hand side is positive.
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another approach for solving problems with >= constraints
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For any greater-than constraints, introduce surplus
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Otherwise, when 337: 311: 282: 241: 72:linear programming 1317: 1316: 1300: 1299: 1240: 1239: 1236: 1235: 1199: 1198: 1160: 1159: 1056: 1055: 1052: 1051: 1048: 1047: 919: 918: 915: 914: 835: 834: 831: 830: 809: 808: 520:, Mark Hutchinson 487:978-0-89871-661-0 476:(26 March 2009). 452:, which apply to 427:{\displaystyle M} 295:ensure that when 114:(as shown below). 76:simplex algorithm 60: 59: 1342: 1246: 1162: 1128: 1105:Branch and bound 1095:Greedy algorithm 1075: 1062: 982: 938: 925: 866: 853: 801:Truncated Newton 716:Wolfe conditions 699: 652: 639: 612: 605: 598: 589: 582: 581: 579: 562:(1): 2455–2468. 547: 518:The Big M Method 512:The Big M Method 491: 433: 431: 430: 425: 413: 411: 410: 405: 372: 370: 369: 364: 346: 344: 343: 338: 320: 318: 317: 312: 291: 289: 288: 283: 250: 248: 247: 242: 55: 52: 46: 27: 26: 19: 1350: 1349: 1345: 1344: 1343: 1341: 1340: 1339: 1320: 1319: 1318: 1313: 1296: 1253: 1232: 1195: 1156: 1133: 1122: 1115: 1069: 1044: 1008: 975: 966: 943: 932: 911: 885: 881:Penalty methods 876:Barrier methods 860: 847: 827: 823:Newton's method 805: 757: 720: 688: 669:Powell's method 646: 633: 616: 586: 585: 549: 548: 544: 539: 504:, Lynn Killen, 488: 471: 463: 440: 416: 415: 375: 374: 349: 348: 323: 322: 297: 296: 256: 255: 218: 217: 206: 186: 179: 159: 128: 122:slack variables 112: 105: 84: 56: 50: 47: 41: 28: 24: 17: 12: 11: 5: 1348: 1346: 1338: 1337: 1335:Linear algebra 1332: 1322: 1321: 1315: 1314: 1312: 1311: 1305: 1302: 1301: 1298: 1297: 1295: 1294: 1289: 1284: 1279: 1274: 1269: 1264: 1258: 1255: 1254: 1251:Metaheuristics 1249: 1242: 1241: 1238: 1237: 1234: 1233: 1231: 1230: 1225: 1223:Ford–Fulkerson 1220: 1215: 1209: 1207: 1201: 1200: 1197: 1196: 1194: 1193: 1191:Floyd–Warshall 1188: 1183: 1182: 1181: 1170: 1168: 1158: 1157: 1155: 1154: 1149: 1144: 1138: 1136: 1125: 1117: 1116: 1114: 1113: 1112: 1111: 1097: 1092: 1087: 1081: 1079: 1071: 1070: 1065: 1058: 1057: 1054: 1053: 1050: 1049: 1046: 1045: 1043: 1042: 1037: 1032: 1027: 1021: 1019: 1010: 1009: 1007: 1006: 1001: 996: 994:Affine scaling 990: 988: 986:Interior point 979: 968: 967: 965: 964: 959: 954: 948: 946: 934: 933: 928: 921: 920: 917: 916: 913: 912: 910: 909: 904: 899: 893: 891: 890:Differentiable 887: 886: 884: 883: 878: 872: 870: 862: 861: 856: 849: 848: 838: 836: 833: 832: 829: 828: 826: 825: 819: 817: 811: 810: 807: 806: 804: 803: 798: 793: 788: 783: 778: 773: 767: 765: 759: 758: 756: 755: 750: 745: 736: 730: 728: 722: 721: 719: 718: 713: 707: 705: 696: 690: 689: 687: 686: 681: 676: 671: 666: 660: 658: 648: 647: 642: 635: 634: 617: 615: 614: 607: 600: 592: 584: 583: 541: 540: 538: 535: 534: 533: 527: 521: 515: 509: 493: 492: 486: 462: 461:External links 459: 458: 457: 447: 439: 436: 423: 403: 400: 397: 394: 391: 388: 385: 382: 362: 359: 356: 336: 333: 330: 310: 307: 304: 293: 292: 281: 278: 275: 272: 269: 266: 263: 252: 251: 240: 237: 234: 231: 228: 225: 205: 202: 189:row reductions 184: 177: 157: 135: 134: 131: 126: 118: 115: 110: 103: 98: 95: 83: 80: 58: 57: 31: 29: 22: 15: 13: 10: 9: 6: 4: 3: 2: 1347: 1336: 1333: 1331: 1328: 1327: 1325: 1310: 1307: 1306: 1303: 1293: 1290: 1288: 1285: 1283: 1280: 1278: 1275: 1273: 1270: 1268: 1267:Hill climbing 1265: 1263: 1260: 1259: 1256: 1252: 1247: 1243: 1229: 1226: 1224: 1221: 1219: 1216: 1214: 1211: 1210: 1208: 1206: 1205:Network flows 1202: 1192: 1189: 1187: 1184: 1180: 1177: 1176: 1175: 1172: 1171: 1169: 1167: 1166:Shortest path 1163: 1153: 1150: 1148: 1145: 1143: 1140: 1139: 1137: 1135: 1134:spanning tree 1129: 1126: 1124: 1118: 1110: 1106: 1103: 1102: 1101: 1098: 1096: 1093: 1091: 1088: 1086: 1083: 1082: 1080: 1076: 1072: 1068: 1067:Combinatorial 1063: 1059: 1041: 1038: 1036: 1033: 1031: 1028: 1026: 1023: 1022: 1020: 1018: 1015: 1011: 1005: 1002: 1000: 997: 995: 992: 991: 989: 987: 983: 980: 978: 973: 969: 963: 960: 958: 955: 953: 950: 949: 947: 945: 939: 935: 931: 926: 922: 908: 905: 903: 900: 898: 895: 894: 892: 888: 882: 879: 877: 874: 873: 871: 867: 863: 859: 854: 850: 842: 824: 821: 820: 818: 816: 812: 802: 799: 797: 794: 792: 789: 787: 784: 782: 779: 777: 774: 772: 769: 768: 766: 764: 763:Other methods 760: 754: 751: 749: 746: 744: 740: 737: 735: 732: 731: 729: 727: 723: 717: 714: 712: 709: 708: 706: 704: 700: 697: 695: 691: 685: 682: 680: 677: 675: 672: 670: 667: 665: 662: 661: 659: 657: 653: 649: 645: 640: 636: 632: 628: 624: 620: 613: 608: 606: 601: 599: 594: 593: 590: 578: 577:11568/1061259 573: 569: 565: 561: 557: 553: 546: 543: 536: 531: 528: 525: 522: 519: 516: 513: 510: 507: 503: 500: 499: 498: 497: 489: 483: 479: 475: 474:Sofer, Ariela 470: 469: 468: 467: 460: 455: 451: 448: 445: 442: 441: 437: 435: 421: 401: 398: 395: 392: 389: 386: 383: 380: 360: 357: 354: 334: 331: 328: 308: 305: 302: 279: 276: 273: 270: 267: 264: 261: 254: 253: 238: 235: 232: 229: 226: 223: 216: 215: 214: 210: 203: 201: 198: 195: 192: 190: 183: 175: 172: +  171: 167: 164: +  163: 156: 153: +  152: 149: +  148: 144: 141: +  140: 137:For example, 132: 129: 123: 119: 116: 113: 106: 99: 96: 93: 92: 91: 88: 81: 79: 77: 73: 69: 65: 54: 44: 39: 35: 32:This article 30: 21: 20: 1272:Local search 1218:Edmonds–Karp 1174:Bellman–Ford 944:minimization 776:Gauss–Newton 726:Quasi–Newton 711:Trust region 619:Optimization 559: 555: 545: 495: 494: 477: 466:Bibliography 465: 464: 294: 211: 207: 199: 196: 193: 181: 173: 169: 165: 161: 154: 150: 146: 142: 138: 136: 124: 108: 101: 89: 85: 68:Big M method 67: 61: 48: 40:for details. 33: 1292:Tabu search 703:Convergence 674:Line search 204:Other usage 36:. See the 1324:Categories 1123:algorithms 631:heuristics 623:Algorithms 537:References 496:Discussion 51:March 2011 1078:Paradigms 977:quadratic 694:Gradients 656:Functions 399:≤ 393:− 387:≤ 381:− 274:− 271:≥ 265:− 233:≤ 227:− 176: âˆ’ s 82:Algorithm 38:talk page 1309:Software 1186:Dijkstra 1017:exchange 815:Hessians 781:Gradient 438:See also 1152:Kruskal 1142:BorĆŻvka 1132:Minimum 869:General 627:methods 373:, then 1014:Basis- 972:Linear 942:Convex 786:Mirror 743:L-BFGS 629:, and 484:  66:, the 1213:Dinic 1121:Graph 321:then 1179:SPFA 1147:Prim 741:and 482:ISBN 1109:cut 974:and 572:hdl 564:doi 62:In 1326:: 625:, 621:: 570:. 560:15 558:. 554:. 180:+ 1107:/ 611:e 604:t 597:v 580:. 574:: 566:: 508:. 490:. 422:M 402:M 396:y 390:x 384:M 361:1 358:= 355:z 335:y 332:= 329:x 309:0 306:= 303:z 280:z 277:M 268:y 262:x 239:z 236:M 230:y 224:x 185:1 182:a 178:1 174:y 170:x 166:y 162:x 158:1 155:s 151:y 147:x 143:y 139:x 127:i 125:s 111:i 109:a 104:i 102:s 53:) 49:(

Index

talk page
WikiProject Mathematics
operations research
linear programming
simplex algorithm
slack variables
row reductions
Two phase method (linear programming)
Karush–Kuhn–Tucker conditions
nonlinear optimization
Sofer, Ariela
ISBN
978-0-89871-661-0
Simplex – Big M Method
Dublin City University
The Big M Method
The Big M Method
The Big-M Method with the Numerical Infinite M
A THREE-PHASE SIMPLEX METHOD FOR INFEASIBLE AND UNBOUNDED LINEAR PROGRAMMING PROBLEMS
"The Big-M method with the numerical infinite M"
doi
10.1007/s11590-020-01644-6
hdl
11568/1061259
v
t
e
Optimization
Algorithms
methods

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