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Feasible region

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of the function being optimized is equated to zero, and any values of the choice variable(s) that satisfy this equation are viewed as candidate solutions (while those that do not are ruled out as candidates). There are several ways in which a candidate solution might not be an actual solution. First,
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feasible set is one in which a line segment connecting any two feasible points goes through only other feasible points, and not through any points outside the feasible set. Convex feasible sets arise in many types of problems, including linear programming problems, and they are of particular
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is selected as the initial candidate solution and is tested for optimality; if it is rejected as the optimum, an adjacent vertex is considered as the next candidate solution. This process is continued until a candidate solution is found to be the optimum.
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The space of all candidate solutions, before any feasible points have been excluded, is called the feasible region, feasible set, search space, or solution space. This is the set of all possible solutions that satisfy the problem's constraints.
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of possible solutions in the feasible region of a given problem. A candidate solution does not have to be a likely or reasonable solution to the problem—it is simply in the set that satisfies all
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If the feasible set is unbounded, there may or may not be an optimum, depending on the specifics of the objective function. For example, if the feasible region is defined by the constraint set {
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A problem with five linear constraints (in blue, including the non-negativity constraints). In the absence of integer constraints the feasible set is the entire region bounded by blue, but with
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constraints on two variables produce a region of possible values for those variables. Solvable two-variable problems will have a feasible region in the shape of a
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If the constraints of an optimization problem are mutually contradictory, there are no points that satisfy all the constraints and thus the feasible region is the
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it might give a minimum when a maximum is being sought (or vice versa), and second, it might give neither a minimum nor a maximum but rather a
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A bounded feasible set (top) and an unbounded feasible set (bottom). The set at the bottom continues forever towards the right.
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if it is bounded. In an algorithm that tests feasible points sequentially, each tested point is in turn a candidate solution.
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In many problems, the feasible set reflects a constraint that one or more variables must be non-negative. In pure
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that is to be maximized, it will generally be easier to solve in the presence of a convex feasible set and any
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is at least 5 and at most 12. The feasible set of the problem is separate from the
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for the feasible set to be bounded is that the number of constraints be at least
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is the set of all possible points (sets of values of the choice variables) of an
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problems, the feasible set is the set of integers (or some subset thereof). In
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has no optimum since any candidate solution can be improved upon by increasing
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Mathematical constraints that define ways of finding the best solution
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to the problem, before the set of candidates has been narrowed down.
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For example, consider the problem of minimizing the function
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is the process of finding a point in the feasible region.
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Optimisation and Stability Theory for Economic Analysis
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This candidate solution is in fact correct except when
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is the process of finding a point in the feasible set.
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In calculus, an optimal solution is sought using the
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This is the initial set of 143: 131: 958: 471:interest because, if the problem has a 14: 1000: 455: 844: 607: 569:≥ 0}, then the problem of maximizing 927: 925: 660: 552:necessary but insufficient condition 546:In linear programming problems with 58:adding citations to reliable sources 29: 503:Bounded and unbounded feasible sets 24: 902:Beavis, Brian; Dobbs, Ian (1990). 486: 25: 1024: 922: 347:{\displaystyle 5\leq y\leq 12.\,} 427:problems, the feasible set is a 34: 645:; that is, it is in the set of 438:whose boundaries are formed by 45:needs additional citations for 961:"A genetic algorithm tutorial" 952: 938:. Cambridge University Press. 895: 749:Cavalieri's quadrature formula 314:{\displaystyle 1\leq x\leq 10} 246:with respect to the variables 148:A closed feasible region of a 13: 1: 888: 747:the candidate solution using 410:{\displaystyle x^{2}+y^{4}.} 7: 672: 585:; yet if the problem is to 239:{\displaystyle x^{2}+y^{4}} 183:that satisfy the problem's 10: 1029: 459: 140:it is the set of red dots. 1013:Mathematical optimization 959:Whitley, Darrell (1994). 473:convex objective function 162:mathematical optimization 968:Statistics and Computing 362:) in which the value of 187:, potentially including 655:Constraint satisfaction 450:Constraint satisfaction 865: 836: 807: 741: 740:{\displaystyle x^{n},} 696:second derivative test 616:and other branches of 512: 442:and whose corners are 436:multidimensional space 411: 348: 315: 283: 260: 240: 157: 141: 852: 837: 835:{\displaystyle n=-1.} 808: 742: 679:first derivative test 515:Feasible sets may be 510: 412: 349: 316: 284: 261: 241: 147: 135: 817: 755: 721: 517:bounded or unbounded 378: 325: 293: 270: 250: 210: 181:optimization problem 54:improve this article 935:Convex Optimization 665:In the case of the 462:Convex optimization 456:Convex feasible set 421:integer programming 201:candidate solutions 138:integer constraints 980:10.1007/BF00175354 874:linear programming 866: 855:linear programming 845:Linear programming 832: 803: 776: 737: 647:feasible solutions 630:candidate solution 608:Candidate solution 513: 425:linear programming 407: 372:objective function 344: 311: 282:{\displaystyle y,} 279: 256: 236: 158: 150:linear programming 142: 1008:Optimal decisions 945:978-0-521-83378-3 775: 667:genetic algorithm 661:Genetic algorithm 622:search algorithms 259:{\displaystyle x} 130: 129: 122: 104: 69:"Feasible region" 16:(Redirected from 1020: 992: 991: 965: 956: 950: 949: 929: 920: 919: 899: 880:of the feasible 841: 839: 838: 833: 812: 810: 809: 804: 793: 792: 777: 774: 760: 746: 744: 743: 738: 733: 732: 692:inflection point 683:first derivative 626:computer science 416: 414: 413: 408: 403: 402: 390: 389: 353: 351: 350: 345: 320: 318: 317: 312: 288: 286: 285: 280: 265: 263: 262: 257: 245: 243: 242: 237: 235: 234: 222: 221: 170:feasible region, 166:computer science 125: 118: 114: 111: 105: 103: 62: 38: 30: 21: 1028: 1027: 1023: 1022: 1021: 1019: 1018: 1017: 998: 997: 996: 995: 963: 957: 953: 946: 930: 923: 916: 900: 896: 891: 847: 818: 815: 814: 782: 778: 764: 758: 756: 753: 752: 728: 724: 722: 719: 718: 711:antiderivatives 675: 663: 610: 505: 489: 487:No feasible set 479:will also be a 464: 458: 398: 394: 385: 381: 379: 376: 375: 326: 323: 322: 294: 291: 290: 271: 268: 267: 251: 248: 247: 230: 226: 217: 213: 211: 208: 207: 126: 115: 109: 106: 63: 61: 51: 39: 28: 23: 22: 15: 12: 11: 5: 1026: 1016: 1015: 1010: 994: 993: 951: 944: 921: 914: 893: 892: 890: 887: 870:simplex method 862:simple polygon 846: 843: 831: 828: 825: 822: 802: 799: 796: 791: 788: 785: 781: 773: 770: 767: 763: 736: 731: 727: 704:global optimum 674: 671: 662: 659: 609: 606: 504: 501: 488: 485: 481:global optimum 457: 454: 434:: a region in 406: 401: 397: 393: 388: 384: 342: 339: 336: 333: 330: 310: 307: 304: 301: 298: 278: 275: 255: 233: 229: 225: 220: 216: 177:solution space 128: 127: 42: 40: 33: 26: 9: 6: 4: 3: 2: 1025: 1014: 1011: 1009: 1006: 1005: 1003: 989: 985: 981: 977: 973: 969: 962: 955: 947: 941: 937: 936: 928: 926: 917: 915:0-521-33605-8 911: 907: 906: 898: 894: 886: 883: 879: 875: 871: 863: 860: 856: 851: 842: 829: 826: 823: 820: 800: 797: 794: 789: 786: 783: 779: 771: 768: 765: 761: 750: 734: 729: 725: 716: 712: 707: 705: 701: 700:local optimum 697: 693: 689: 684: 680: 670: 668: 658: 656: 650: 648: 644: 639: 635: 631: 627: 624:(a topic in 623: 619: 615: 605: 604:) = (0, 0)). 603: 599: 595: 591: 588: 584: 580: 576: 572: 568: 564: 559: 557: 553: 550:variables, a 549: 544: 542: 538: 534: 530: 526: 522: 518: 509: 500: 498: 494: 484: 482: 478: 477:local optimum 474: 469: 463: 453: 451: 447: 445: 441: 437: 433: 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taking 702:but not a 497:infeasible 460:See also: 193:equalities 154:polyhedron 80:newspapers 827:− 751:would be 715:monomials 620:, and in 493:empty set 338:≤ 332:≤ 306:≤ 300:≤ 882:polytope 673:Calculus 587:minimize 444:vertices 432:polytope 988:3447126 868:In the 636:of the 197:integer 94:scholar 986:  942:  912:  878:vertex 859:convex 690:or an 681:: the 634:member 468:convex 429:convex 195:, and 96:  89:  82:  75:  67:  984:S2CID 964:(PDF) 632:is a 628:), a 565:≥ 0, 535:≥ 0, 531:≥ 0, 523:≥ 0, 101:JSTOR 87:books 940:ISBN 910:ISBN 321:and 266:and 168:, a 164:and 73:news 976:doi 713:of 638:set 612:In 581:or 539:+ 2 341:12. 175:or 160:In 56:by 1004:: 982:. 970:. 966:. 924:^ 830:1. 706:. 600:, 592:+ 573:+ 499:. 483:. 466:A 446:. 358:, 309:10 191:, 990:. 978:: 972:4 948:. 918:. 824:= 821:n 801:. 798:C 795:+ 790:1 787:+ 784:n 780:x 772:1 769:+ 766:n 762:1 735:, 730:n 726:x 602:y 598:x 594:y 590:x 583:y 579:x 575:y 571:x 567:y 563:x 556:n 548:n 541:y 537:x 533:y 529:x 525:y 521:x 405:. 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Index

Feasible set

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integer constraints

linear programming
polyhedron
mathematical optimization
computer science
optimization problem
constraints
inequalities
equalities
integer
candidate solutions
objective function
integer programming
linear programming
convex
polytope

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