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Column generation

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2185: 1655: 2180:{\displaystyle {\begin{aligned}{\frac {\partial z_{\hat {y}}^{*}}{\partial {\hat {y}}}}&~=~&&c_{y}+{\frac {\partial z^{*}}{\partial {\hat {y}}}}\\&~=~&&c_{y}+{\frac {\partial z^{*}}{\partial c}}{\frac {dc}{d{\hat {y}}}}+{\frac {\partial z^{*}}{\partial A}}{\frac {dA}{d{\hat {y}}}}+{\frac {\partial z^{*}}{\partial b}}{\frac {db}{d{\hat {y}}}}\\&~=~&&c_{y}+{\frac {\partial z^{*}}{\partial b}}{\frac {db}{d{\hat {y}}}}\\&~=~&&c_{y}+u^{*}(-A_{y})\\&~=~&&c_{y}-u^{*}A_{y}\end{aligned}}} 233:
problem called the pricing subproblem which strongly depends on the structure of the original problem. The objective function of the subproblem is the reduced cost of the searched variable with respect to the current dual variables, and the constraints require that the variable obeys the naturally occurring constraints. The column generation method is particularly efficient when this structure makes it possible to solve the sub-problem with an efficient algorithm, typically a dedicated
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When the number of variables is very large, it is not possible to find an improving variable by calculating all the reduced cost and choosing a variable with a negative reduced cost. Thus, the idea is to compute only the variable having the minimum reduced cost. This can be done using an optimization
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are added to the program. Once it is possible to demonstrate that adding new variables would no longer improve the value of the objective function, the procedure stops. The hope when applying a column generation algorithm is that only a very small fraction of the variables will be generated. This
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The overarching idea is that many linear programs are too large to consider all the variables explicitly. The idea is thus to start by solving the considered program with only a subset of its variables. Then iteratively, variables that have the potential to improve the
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The algorithm considers two problems: the master problem and the subproblem. The master problem is the original problem with only a subset of variables being considered. The subproblem is a new problem created to identify an improving variable
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translates into two terms. First, this change directly impacts the objective function and second, the right-hand side of the constraints is modified which has an impact on the optimal variables
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In many cases, this method allows to solve large linear programs that would otherwise be intractable. The classical example of a problem where it is successfully used is the
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hope is supported by the fact that in the optimal solution, most variables will be non-basic and assume a value of zero, so the optimal solution can be found without them.
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be optimal solutions for these two problems which can be provided by any linear solver. These solutions verify the constraints of their linear program and, by
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that the problem is a minimization problem). If no variable has a negative reduced cost, then the current solution of the master problem is optimal.
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We now detail how and why to compute the reduced cost of the variables. Consider the following linear program in standard form:
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was present in the model but took a zero value. We will now observe the impact on the primal problem of changing the value of
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was not considered until then in the primal problem. Note that this is equivalent to saying that the variable
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indicates by how much increases locally the optimal value of the objective function when the coefficient
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for each constraint of the primal linear model. It is possible to show that an optimal dual variable
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can be expressed according to the value of the objective function of the initial primal problem:
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in the objective function and in the constraints then the linear program is modified as follows:
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The most difficult part of this procedure is how to find a variable that can improve the
156:. One particular technique in linear programming which uses this kind of approach is the 603:. This optimal value is a function of the different coefficients of the primal problem: 3191: 2959: 2844: 2731: 2665: 2636: 2384: 1405: 1313: 1136: 1033: 1013: 993: 973: 348: 221:
of the master problem. This can be done by finding the variable with the most negative
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algorithm. Additionally, column generation has been applied to many problems such as
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If an improving variable is found: add it to the master problem then go to step 2
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of the objective function of this new problem decreases as the value
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can be interpreted as the partial derivative of the optimal value
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to let it take a non-zero value), we want to know if the value
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are respectively the coefficients associated with the variable
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In order to know if it is interesting to add the variable
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of the objective function with respect to the coefficient
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Else: The solution of the master problem is optimal. Stop.
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whose magnitude is measured using the dual variables
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Search for an improving variable with the subproblem
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Unsourced material may be challenged and 3222: 3208: 3096: 3012: 2978: 2925: 2912: 2832: 2788: 2775: 2716: 2703: 2549: 2502: 2489: 2461: 2447: 2439: 782:of the right-hand side of the constraints: 2415: 2406: 2386: 2353: 2352: 2341: 2330: 2329: 2319: 2317: 2296: 2290: 2269: 2263: 2242: 2231: 2230: 2224: 2198: 2197: 2195: 2167: 2157: 2144: 2114: 2098: 2085: 2050: 2049: 2035: 2018: 2008: 1999: 1964: 1963: 1949: 1932: 1922: 1905: 1904: 1890: 1873: 1863: 1846: 1845: 1831: 1814: 1804: 1795: 1760: 1759: 1748: 1738: 1729: 1697: 1696: 1685: 1674: 1673: 1663: 1659: 1657: 1625: 1624: 1618: 1587: 1569: 1568: 1562: 1549: 1538: 1537: 1531: 1510: 1499: 1498: 1492: 1463: 1462: 1451: 1440: 1439: 1429: 1427: 1407: 1381: 1380: 1378: 1357: 1346: 1345: 1339: 1315: 1287: 1283: 1282: 1259: 1258: 1252: 1223: 1207: 1206: 1200: 1184: 1174: 1163: 1161: 1138: 1117: 1111: 1090: 1084: 1058: 1057: 1055: 1035: 1015: 995: 975: 951: 945: 924: 919: 913: 881: 871: 862: 856: 832: 817: 807: 798: 793: 787: 766: 760: 739: 733: 712: 707: 701: 680: 675: 669: 664:. Note that there exists a dual variable 627: 614: 608: 587: 581: 554: 541: 531: 525: 500: 494: 473: 467: 441: 440: 414: 400: 386: 376: 365: 363: 324: 320: 319: 285: 271: 261: 250: 248: 117:Learn how and when to remove this message 2695:Optimization computes maxima and minima. 192:The algorithm then proceeds as follow: 2891:Principal pivoting algorithm of Lemke 16:Algorithm for solving linear programs 7: 3176: 3174: 51:adding citations to reliable sources 3241:Optimization algorithms and methods 2535:Successive parabolic interpolation 2349: 2322: 2026: 2011: 1940: 1925: 1881: 1866: 1822: 1807: 1756: 1741: 1693: 1666: 1459: 1432: 889: 874: 825: 810: 657:{\displaystyle z^{*}=z^{*}(c,A,b)} 569:{\displaystyle c^{T}x^{*}=u^{*T}b} 14: 2855:Projective algorithm of Karmarkar 3178: 2850:Ellipsoid algorithm of Khachiyan 2753:Sequential quadratic programming 2590:Broyden–Fletcher–Goldfarb–Shanno 2251:{\displaystyle z_{\hat {y}}^{*}} 1519:{\displaystyle z_{\hat {y}}^{*}} 1366:{\displaystyle z_{\hat {y}}^{*}} 23: 2808:Reduced gradient (Frank–Wolfe) 2358: 2335: 2236: 2203: 2120: 2104: 2055: 1969: 1910: 1851: 1765: 1702: 1679: 1636: 1630: 1593: 1574: 1543: 1504: 1468: 1445: 1386: 1351: 1264: 1212: 1063: 651: 633: 1: 3138:Spiral optimization algorithm 2758:Successive linear programming 970:Consider now that a variable 213:Finding an improving variable 3194:. You can help Knowledge by 2876:Simplex algorithm of Dantzig 2748:Augmented Lagrangian methods 170:capacitated p-median problem 158:Dantzig–Wolfe decomposition 3262: 3173: 2212:{\displaystyle {\hat {y}}} 1395:{\displaystyle {\hat {y}}} 1072:{\displaystyle {\hat {y}}} 227:without loss of generality 3246:Applied mathematics stubs 3155: 3108: 3095: 3079:Push–relabel maximum flow 2924: 2911: 2881:Revised simplex algorithm 2787: 2774: 2715: 2702: 2688: 2501: 2488: 933:{\displaystyle u_{i}^{*}} 721:{\displaystyle u_{i}^{*}} 689:{\displaystyle u_{i}^{*}} 189:of the master problem). 134:delayed column generation 2604:Symmetric rank-one (SR1) 2585:Berndt–Hall–Hall–Hausman 2377:is generally called the 1487:. To do this, note that 199:Solve the master problem 3128:Parallel metaheuristics 2936:Approximation algorithm 2647:Powell's dog leg method 2599:Davidon–Fletcher–Powell 2495:Unconstrained nonlinear 2401:and will be denoted by 967:increases by one unit. 347:which we will call the 235:combinatorial algorithm 3190:-related article is a 3113:Evolutionary algorithm 2696: 2425: 2424:{\displaystyle cr_{y}} 2395: 2371: 2306: 2279: 2252: 2213: 2181: 1643: 1520: 1481: 1416: 1396: 1367: 1324: 1301: 1147: 1127: 1100: 1073: 1044: 1024: 1004: 984: 961: 934: 902: 845: 776: 749: 722: 690: 658: 597: 570: 510: 483: 453: 338: 185:which can improve the 2886:Criss-cross algorithm 2709:Constrained nonlinear 2694: 2515:Golden-section search 2426: 2396: 2372: 2307: 2305:{\displaystyle u^{*}} 2280: 2278:{\displaystyle x^{*}} 2253: 2214: 2182: 1644: 1521: 1482: 1417: 1397: 1368: 1325: 1302: 1148: 1128: 1126:{\displaystyle A_{y}} 1101: 1099:{\displaystyle c_{y}} 1074: 1045: 1025: 1005: 985: 962: 960:{\displaystyle b_{i}} 935: 903: 846: 777: 775:{\displaystyle b_{i}} 750: 748:{\displaystyle z^{*}} 723: 691: 659: 598: 596:{\displaystyle z^{*}} 576:) which we will call 571: 511: 509:{\displaystyle u^{*}} 484: 482:{\displaystyle x^{*}} 454: 339: 154:cutting stock problem 2803:Cutting-plane method 2405: 2385: 2316: 2289: 2262: 2223: 2194: 1656: 1530: 1491: 1426: 1406: 1377: 1338: 1314: 1160: 1137: 1110: 1083: 1054: 1034: 1014: 994: 974: 944: 912: 855: 786: 759: 732: 700: 668: 607: 580: 524: 493: 466: 362: 247: 47:improve this article 3188:applied mathematics 3133:Simulated annealing 2951:Integer programming 2941:Dynamic programming 2781:Convex optimization 2642:Levenberg–Marquardt 2346: 2247: 1690: 1554: 1515: 1456: 1362: 929: 908:. More simply put, 803: 717: 685: 353:dual linear program 66:"Column generation" 2813:Subgradient method 2697: 2622:Conjugate gradient 2530:Nelder–Mead method 2431:in the following. 2421: 2391: 2367: 2325: 2302: 2275: 2248: 2226: 2209: 2177: 2175: 1669: 1639: 1533: 1516: 1494: 1477: 1435: 1412: 1392: 1363: 1341: 1320: 1297: 1295: 1179: 1143: 1123: 1096: 1069: 1040: 1020: 1000: 980: 957: 930: 915: 898: 841: 789: 772: 745: 718: 703: 686: 671: 654: 593: 566: 506: 479: 449: 447: 381: 334: 332: 266: 219:objective function 187:objective function 146:objective function 3203: 3202: 3168: 3167: 3151: 3150: 3091: 3090: 3087: 3086: 3050: 3049: 3011: 3010: 2907: 2906: 2903: 2902: 2899: 2898: 2770: 2769: 2766: 2765: 2686: 2685: 2682: 2681: 2660: 2659: 2394:{\displaystyle y} 2365: 2361: 2338: 2312:. The derivative 2239: 2206: 2136: 2130: 2077: 2071: 2062: 2058: 2033: 1991: 1985: 1976: 1972: 1947: 1917: 1913: 1888: 1858: 1854: 1829: 1787: 1781: 1772: 1768: 1721: 1715: 1709: 1705: 1682: 1633: 1577: 1546: 1507: 1475: 1471: 1448: 1415:{\displaystyle y} 1389: 1354: 1323:{\displaystyle y} 1267: 1226: 1215: 1170: 1146:{\displaystyle y} 1066: 1043:{\displaystyle 0} 1023:{\displaystyle y} 1003:{\displaystyle y} 983:{\displaystyle y} 896: 839: 403: 372: 288: 257: 130:Column generation 127: 126: 119: 101: 3253: 3224: 3217: 3210: 3182: 3175: 3097: 3013: 2979: 2956:Branch and bound 2946:Greedy algorithm 2926: 2913: 2833: 2789: 2776: 2717: 2704: 2652:Truncated Newton 2567:Wolfe conditions 2550: 2503: 2490: 2463: 2456: 2449: 2440: 2430: 2428: 2427: 2422: 2420: 2419: 2400: 2398: 2397: 2392: 2381:of the variable 2376: 2374: 2373: 2368: 2366: 2364: 2363: 2362: 2354: 2347: 2345: 2340: 2339: 2331: 2320: 2311: 2309: 2308: 2303: 2301: 2300: 2284: 2282: 2281: 2276: 2274: 2273: 2257: 2255: 2254: 2249: 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3140: 3135: 3130: 3125: 3120: 3115: 3109: 3106: 3105: 3102:Metaheuristics 3100: 3093: 3092: 3089: 3088: 3085: 3084: 3082: 3081: 3076: 3074:Ford–Fulkerson 3071: 3066: 3060: 3058: 3052: 3051: 3048: 3047: 3045: 3044: 3042:Floyd–Warshall 3039: 3034: 3033: 3032: 3021: 3019: 3009: 3008: 3006: 3005: 3000: 2995: 2989: 2987: 2976: 2968: 2967: 2965: 2964: 2963: 2962: 2948: 2943: 2938: 2932: 2930: 2922: 2921: 2916: 2909: 2908: 2905: 2904: 2901: 2900: 2897: 2896: 2894: 2893: 2888: 2883: 2878: 2872: 2870: 2861: 2860: 2858: 2857: 2852: 2847: 2845:Affine scaling 2841: 2839: 2837:Interior point 2830: 2819: 2818: 2816: 2815: 2810: 2805: 2799: 2797: 2785: 2784: 2779: 2772: 2771: 2768: 2767: 2764: 2763: 2761: 2760: 2755: 2750: 2744: 2742: 2741:Differentiable 2738: 2737: 2735: 2734: 2729: 2723: 2721: 2713: 2712: 2707: 2700: 2699: 2689: 2687: 2684: 2683: 2680: 2679: 2677: 2676: 2670: 2668: 2662: 2661: 2658: 2657: 2655: 2654: 2649: 2644: 2639: 2634: 2629: 2624: 2618: 2616: 2610: 2609: 2607: 2606: 2601: 2596: 2587: 2581: 2579: 2573: 2572: 2570: 2569: 2564: 2558: 2556: 2547: 2541: 2540: 2538: 2537: 2532: 2527: 2522: 2517: 2511: 2509: 2499: 2498: 2493: 2486: 2485: 2468: 2466: 2465: 2458: 2451: 2443: 2436: 2433: 2418: 2414: 2410: 2390: 2360: 2357: 2351: 2344: 2337: 2334: 2328: 2324: 2299: 2295: 2272: 2268: 2245: 2238: 2235: 2229: 2205: 2202: 2188: 2187: 2170: 2166: 2160: 2156: 2152: 2147: 2143: 2139: 2133: 2127: 2125: 2122: 2117: 2113: 2109: 2106: 2101: 2097: 2093: 2088: 2084: 2080: 2074: 2068: 2066: 2057: 2054: 2048: 2043: 2040: 2031: 2028: 2021: 2017: 2013: 2007: 2002: 1998: 1994: 1988: 1982: 1980: 1971: 1968: 1962: 1957: 1954: 1945: 1942: 1935: 1931: 1927: 1921: 1912: 1909: 1903: 1898: 1895: 1886: 1883: 1876: 1872: 1868: 1862: 1853: 1850: 1844: 1839: 1836: 1827: 1824: 1817: 1813: 1809: 1803: 1798: 1794: 1790: 1784: 1778: 1776: 1767: 1764: 1758: 1751: 1747: 1743: 1737: 1732: 1728: 1724: 1718: 1712: 1704: 1701: 1695: 1688: 1681: 1678: 1672: 1668: 1662: 1661: 1638: 1632: 1629: 1621: 1617: 1613: 1610: 1607: 1604: 1601: 1598: 1595: 1590: 1586: 1582: 1576: 1573: 1565: 1561: 1557: 1552: 1545: 1542: 1536: 1513: 1506: 1503: 1497: 1470: 1467: 1461: 1454: 1447: 1444: 1438: 1434: 1411: 1388: 1385: 1360: 1353: 1350: 1344: 1319: 1308: 1307: 1290: 1285: 1280: 1277: 1274: 1272: 1266: 1263: 1255: 1251: 1247: 1244: 1241: 1238: 1235: 1232: 1230: 1222: 1220: 1214: 1211: 1203: 1199: 1195: 1192: 1187: 1183: 1177: 1173: 1169: 1167: 1165: 1142: 1120: 1116: 1093: 1089: 1065: 1062: 1039: 1019: 999: 979: 954: 950: 927: 922: 918: 894: 891: 884: 880: 876: 870: 865: 861: 835: 831: 827: 820: 816: 812: 806: 801: 796: 792: 769: 765: 742: 738: 715: 710: 706: 683: 678: 674: 653: 650: 647: 644: 641: 638: 635: 630: 626: 622: 617: 613: 590: 586: 565: 560: 557: 553: 549: 544: 540: 534: 530: 503: 499: 476: 472: 462:Moreover, let 460: 459: 443: 439: 436: 433: 431: 428: 425: 422: 417: 413: 409: 407: 399: 397: 394: 389: 385: 379: 375: 371: 369: 367: 349:primal problem 345: 344: 327: 322: 317: 314: 311: 309: 306: 303: 300: 297: 294: 292: 284: 282: 279: 274: 270: 264: 260: 256: 254: 252: 214: 211: 210: 209: 206: 203: 200: 197: 177: 174: 125: 124: 31: 29: 22: 15: 13: 10: 9: 6: 4: 3: 2: 3258: 3247: 3244: 3242: 3239: 3238: 3236: 3225: 3220: 3218: 3213: 3211: 3206: 3205: 3199: 3197: 3193: 3189: 3184: 3181: 3177: 3172: 3161: 3158: 3157: 3154: 3144: 3141: 3139: 3136: 3134: 3131: 3129: 3126: 3124: 3121: 3119: 3118:Hill climbing 3116: 3114: 3111: 3110: 3107: 3103: 3098: 3094: 3080: 3077: 3075: 3072: 3070: 3067: 3065: 3062: 3061: 3059: 3057: 3056:Network flows 3053: 3043: 3040: 3038: 3035: 3031: 3028: 3027: 3026: 3023: 3022: 3020: 3018: 3017:Shortest path 3014: 3004: 3001: 2999: 2996: 2994: 2991: 2990: 2988: 2986: 2985:spanning tree 2980: 2977: 2975: 2969: 2961: 2957: 2954: 2953: 2952: 2949: 2947: 2944: 2942: 2939: 2937: 2934: 2933: 2931: 2927: 2923: 2919: 2918:Combinatorial 2914: 2910: 2892: 2889: 2887: 2884: 2882: 2879: 2877: 2874: 2873: 2871: 2869: 2866: 2862: 2856: 2853: 2851: 2848: 2846: 2843: 2842: 2840: 2838: 2834: 2831: 2829: 2824: 2820: 2814: 2811: 2809: 2806: 2804: 2801: 2800: 2798: 2796: 2790: 2786: 2782: 2777: 2773: 2759: 2756: 2754: 2751: 2749: 2746: 2745: 2743: 2739: 2733: 2730: 2728: 2725: 2724: 2722: 2718: 2714: 2710: 2705: 2701: 2693: 2675: 2672: 2671: 2669: 2667: 2663: 2653: 2650: 2648: 2645: 2643: 2640: 2638: 2635: 2633: 2630: 2628: 2625: 2623: 2620: 2619: 2617: 2615: 2614:Other methods 2611: 2605: 2602: 2600: 2597: 2595: 2591: 2588: 2586: 2583: 2582: 2580: 2578: 2574: 2568: 2565: 2563: 2560: 2559: 2557: 2555: 2551: 2548: 2546: 2542: 2536: 2533: 2531: 2528: 2526: 2523: 2521: 2518: 2516: 2513: 2512: 2510: 2508: 2504: 2500: 2496: 2491: 2487: 2483: 2479: 2475: 2471: 2464: 2459: 2457: 2452: 2450: 2445: 2444: 2441: 2434: 2432: 2416: 2412: 2408: 2388: 2380: 2355: 2342: 2332: 2326: 2297: 2293: 2270: 2266: 2243: 2233: 2227: 2219:on the value 2200: 2168: 2164: 2158: 2154: 2150: 2145: 2141: 2131: 2115: 2111: 2107: 2099: 2095: 2091: 2086: 2082: 2072: 2052: 2046: 2041: 2038: 2029: 2019: 2015: 2005: 2000: 1996: 1986: 1966: 1960: 1955: 1952: 1943: 1933: 1929: 1919: 1907: 1901: 1896: 1893: 1884: 1874: 1870: 1860: 1848: 1842: 1837: 1834: 1825: 1815: 1811: 1801: 1796: 1792: 1782: 1762: 1749: 1745: 1735: 1730: 1726: 1716: 1699: 1686: 1676: 1670: 1652: 1651: 1650: 1627: 1619: 1615: 1611: 1608: 1605: 1602: 1599: 1596: 1588: 1584: 1580: 1571: 1563: 1559: 1555: 1550: 1540: 1534: 1511: 1501: 1495: 1465: 1452: 1442: 1436: 1409: 1383: 1358: 1348: 1342: 1333: 1317: 1288: 1278: 1275: 1261: 1253: 1249: 1245: 1242: 1239: 1236: 1233: 1209: 1201: 1197: 1193: 1190: 1185: 1181: 1175: 1168: 1156: 1155: 1154: 1140: 1118: 1114: 1091: 1087: 1060: 1037: 1017: 997: 977: 968: 952: 948: 925: 920: 916: 892: 882: 878: 868: 863: 859: 851:or otherwise 833: 829: 818: 814: 804: 799: 794: 790: 767: 763: 740: 736: 713: 708: 704: 681: 676: 672: 648: 645: 642: 639: 636: 628: 624: 620: 615: 611: 588: 584: 563: 558: 555: 551: 547: 542: 538: 532: 528: 519: 501: 497: 474: 470: 437: 434: 426: 423: 420: 415: 411: 392: 387: 383: 377: 370: 358: 357: 356: 354: 350: 325: 315: 312: 304: 301: 298: 295: 277: 272: 268: 262: 255: 243: 242: 241: 238: 236: 230: 228: 224: 220: 212: 207: 204: 201: 198: 195: 194: 193: 190: 188: 184: 175: 173: 171: 167: 163: 159: 155: 150: 147: 141: 139: 135: 131: 121: 118: 110: 99: 96: 92: 89: 85: 82: 78: 75: 71: 68: â€“  67: 63: 62:Find sources: 56: 52: 48: 42: 41: 37: 32:This article 30: 26: 21: 20: 3196:expanding it 3185: 3170: 3123:Local search 3069:Edmonds–Karp 3025:Bellman–Ford 2795:minimization 2627:Gauss–Newton 2577:Quasi–Newton 2562:Trust region 2470:Optimization 2379:reduced cost 2189: 1331: 1309: 969: 461: 346: 239: 231: 223:reduced cost 216: 191: 182: 179: 151: 142: 133: 129: 128: 113: 104: 94: 87: 80: 73: 61: 45:Please help 33: 3143:Tabu search 2554:Convergence 2525:Line search 3235:Categories 2974:algorithms 2482:heuristics 2474:Algorithms 2435:References 1225:subject to 402:subject to 287:subject to 225:(assuming 168:, and the 77:newspapers 2929:Paradigms 2828:quadratic 2545:Gradients 2507:Functions 2359:^ 2350:∂ 2343:∗ 2336:^ 2323:∂ 2298:∗ 2271:∗ 2244:∗ 2237:^ 2204:^ 2159:∗ 2151:− 2108:− 2100:∗ 2056:^ 2027:∂ 2020:∗ 2012:∂ 1970:^ 1941:∂ 1934:∗ 1926:∂ 1911:^ 1882:∂ 1875:∗ 1867:∂ 1852:^ 1823:∂ 1816:∗ 1808:∂ 1766:^ 1757:∂ 1750:∗ 1742:∂ 1703:^ 1694:∂ 1687:∗ 1680:^ 1667:∂ 1631:^ 1612:− 1589:∗ 1575:^ 1551:∗ 1544:^ 1512:∗ 1505:^ 1469:^ 1460:∂ 1453:∗ 1446:^ 1433:∂ 1387:^ 1359:∗ 1352:^ 1279:∈ 1265:^ 1246:− 1213:^ 1064:^ 926:∗ 890:∂ 883:∗ 875:∂ 864:∗ 826:∂ 819:∗ 811:∂ 800:∗ 741:∗ 714:∗ 682:∗ 629:∗ 616:∗ 589:∗ 556:∗ 543:∗ 502:∗ 475:∗ 438:∈ 424:≤ 316:∈ 176:Algorithm 34:does not 3160:Software 3037:Dijkstra 2868:exchange 2666:Hessians 2632:Gradient 107:May 2024 3003:Kruskal 2993:BorĹŻvka 2983:Minimum 2720:General 2478:methods 518:duality 91:scholar 55:removed 40:sources 2865:Basis- 2823:Linear 2793:Convex 2637:Mirror 2594:L-BFGS 2480:, and 2135:  2129:  2076:  2070:  1990:  1984:  1786:  1780:  1720:  1714:  93:  86:  79:  72:  64:  3186:This 3064:Dinic 2972:Graph 1079:. If 1030:from 98:JSTOR 84:books 3192:stub 3030:SPFA 2998:Prim 2592:and 1106:and 489:and 183:i.e. 70:news 38:any 36:cite 2960:cut 2825:and 1332:i.e 1172:min 1050:to 374:max 259:min 132:or 49:by 3237:: 2476:, 2472:: 355:: 237:. 172:. 164:, 140:. 3223:e 3216:t 3209:v 3198:. 2958:/ 2462:e 2455:t 2448:v 2417:y 2413:r 2409:c 2389:y 2356:y 2333:y 2327:z 2294:u 2267:x 2234:y 2228:z 2201:y 2169:y 2165:A 2155:u 2146:y 2142:c 2132:= 2121:) 2116:y 2112:A 2105:( 2096:u 2092:+ 2087:y 2083:c 2073:= 2053:y 2047:d 2042:b 2039:d 2030:b 2016:z 2006:+ 2001:y 1997:c 1987:= 1967:y 1961:d 1956:b 1953:d 1944:b 1930:z 1920:+ 1908:y 1902:d 1897:A 1894:d 1885:A 1871:z 1861:+ 1849:y 1843:d 1838:c 1835:d 1826:c 1812:z 1802:+ 1797:y 1793:c 1783:= 1763:y 1746:z 1736:+ 1731:y 1727:c 1717:= 1700:y 1677:y 1671:z 1637:) 1628:y 1620:y 1616:A 1609:b 1606:, 1603:A 1600:, 1597:c 1594:( 1585:z 1581:+ 1572:y 1564:y 1560:c 1556:= 1541:y 1535:z 1502:y 1496:z 1466:y 1443:y 1437:z 1410:y 1384:y 1349:y 1343:z 1318:y 1289:+ 1284:R 1276:x 1262:y 1254:y 1250:A 1243:b 1240:= 1237:x 1234:A 1210:y 1202:y 1198:c 1194:+ 1191:x 1186:T 1182:c 1176:x 1141:y 1119:y 1115:A 1092:y 1088:c 1061:y 1038:0 1018:y 998:y 978:y 953:i 949:b 921:i 917:u 893:b 879:z 869:= 860:u 834:i 830:b 815:z 805:= 795:i 791:u 768:i 764:b 737:z 709:i 705:u 677:i 673:u 652:) 649:b 646:, 643:A 640:, 637:c 634:( 625:z 621:= 612:z 585:z 564:b 559:T 552:u 548:= 539:x 533:T 529:c 498:u 471:x 442:R 435:u 427:c 421:A 416:T 412:u 393:b 388:T 384:u 378:u 326:+ 321:R 313:x 305:b 302:= 299:x 296:A 278:x 273:T 269:c 263:x 181:( 120:) 114:( 109:) 105:( 95:· 88:· 81:· 74:· 57:. 43:.

Index


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"Column generation"
news
newspapers
books
scholar
JSTOR
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linear programs
objective function
cutting stock problem
Dantzig–Wolfe decomposition
crew scheduling
vehicle routing
capacitated p-median problem
objective function
objective function
reduced cost
without loss of generality
combinatorial algorithm
primal problem
dual linear program
duality
reduced cost
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