// Copyright (C) 2015 - IIT Bombay - FOSSEE
//
// Author: Harpreet Singh
// Organization: FOSSEE, IIT Bombay
// Email: harpreet.mertia@gmail.com
// This file must be used under the terms of the CeCILL.
// This source file is licensed as described in the file COPYING, which
// you should have received as part of this distribution.  The terms
// are also available at
// http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt

function [xopt,fopt,status,output] = symphony (varargin)
  // Solves a  mixed integer linear programming constrained optimization problem.
  //
  //   Calling Sequence
  //   xopt = symphony(nbVar,nbCon,objCoef,isInt,LB,UB,conMatrix,conLB,conUB)
  //   xopt = symphony(nbVar,nbCon,objCoef,isInt,LB,UB,conMatrix,conLB,conUB,objSense)
  //   xopt = symphony(nbVar,nbCon,objCoef,isInt,LB,UB,conMatrix,conLB,conUB,objSense,options)
  //   [xopt,fopt,status,output] = symphony( ... )
  //   
  //   Parameters
  //   nbVar : a double, number of variables.
  //   nbCon : a double, number of constraints.
  //   objCoeff : a 1 x n matrix of doubles, where n is number of variables, represents coefficients of the variables in the objective.
  //   isInt : a vector of boolean, represents wether a variable is constrained to be an integer.
  //   LB : a vector of doubles, represents lower bounds of the variables.
  //   UB : a vector of doubles, represents upper bounds of the variables.
  //   conMatrix : a matrix of doubles, represents  matrix representing the constraint matrix.
  //   conLB : a vector of doubles, represents lower bounds of the constraints. 
  //   conUB : a vector of doubles, represents upper bounds of the constraints
  //   objSense : The sense (maximization/minimization) of the objective. Use 1(sym_minimize ) or -1 (sym_maximize) here.
  //   options : a a list containing the the parameters to be set.
  //   xopt : a vector of doubles, the computed solution of the optimization problem.
  //   fopt : a double, the function value at x.
  //   status : status flag from symphony.
  //   output : The output data structure contains detailed informations about the optimization process.
  //   
  //   Description
  //   Search the minimum or maximum of a constrained mixed integer linear programming optimization problem specified by :
  //   find the minimum or maximum of f(x) such that 
  //
  //   <latex>
  //    \begin{eqnarray}
  //    &\mbox{min}_{x}
  //    & f(x) \\
  //    & \text{subject to} & conLB \leq C(x) \leq conUB \\
  //    & & lb \leq x \leq ub \\
  //    \end{eqnarray}
  //   </latex>
  //   
  //   We are calling SYMPHONY written in C by gateway files for the actual computation. SYMPHONY was originally written by ​Ted Ralphs, ​Menal Guzelsoy and ​Ashutosh Mahajan.
  //
  //   Examples
  //    //A basic case : 
  //    // Objective function
  //    c = [350*5,330*3,310*4,280*6,500,450,400,100]';
  //    // Lower Bound of variable
  //    lb = repmat(0,8,1);
  //    // Upper Bound of variables
  //    ub = [repmat(1,4,1);repmat(%inf,4,1)];
  //    // Constraint Matrix
  //    conMatrix = [5,3,4,6,1,1,1,1;
  //                 5*0.05,3*0.04,4*0.05,6*0.03,0.08,0.07,0.06,0.03;
  //                 5*0.03,3*0.03,4*0.04,6*0.04,0.06,0.07,0.08,0.09;]
  //    // Lower Bound of constrains
  //    conlb = [ 25; 1.25; 1.25]
  //    // Upper Bound of constrains
  //    conub = [ 25; 1.25; 1.25]
  //    // Row Matrix for telling symphony that the is integer or not
  //    isInt = [repmat(%t,1,4) repmat(%f,1,4)];
  //    xopt = [1 1 0 1 7.25 0 0.25 3.5]
  //    fopt = [8495]
  //    // Calling Symphony
  //    [x,f,status,output] = symphony(8,3,c,isInt,lb,ub,conMatrix,conlb,conub,1)
  //
    //    Examples
    //    // An advanced case where we set some options in symphony
    //    // This problem is taken from 
    //    // P.C.Chu and J.E.Beasley 
    //    // "A genetic algorithm for the multidimensional knapsack problem",
    //    // Journal of Heuristics, vol. 4, 1998, pp63-86.
    //    // The problem to be solved is:
    //    // Max  sum{j=1,...,n} p(j)x(j)
    //    // st   sum{j=1,...,n} r(i,j)x(j) <= b(i)       i=1,...,m
    //    //                     x(j)=0 or 1
    //    // The function to be maximize i.e. P(j)
    //    p = [   504 803 667 1103 834 585 811 856 690 832 846 813 868 793 ..
    //            825 1002 860 615 540 797 616 660 707 866 647 746 1006 608 ..
    //            877 900 573 788 484 853 942 630 591 630 640 1169 932 1034 ..
    //            957 798 669 625 467 1051 552 717 654 388 559 555 1104 783 ..
    //            959 668 507 855 986 831 821 825 868 852 832 828 799 686 ..
    //            510 671 575 740 510 675 996 636 826 1022 1140 654 909 799 ..
    //            1162 653 814 625 599 476 767 954 906 904 649 873 565 853 1008 632]';
    //    //Constraint Matrix
    //    conMatrix = [ 
    //                    //Constraint 1
    //                    42 41 523 215 819 551 69 193 582 375 367 478 162 898 ..
    //                    550 553 298 577 493 183 260 224 852 394 958 282 402 604 ..
    //                    164 308 218 61 273 772 191 117 276 877 415 873 902 465 ..
    //                    320 870 244 781 86 622 665 155 680 101 665 227 597 354 ..
    //                    597 79 162 998 849 136 112 751 735 884 71 449 266 420 ..
    //                    797 945 746 46 44 545 882 72 383 714 987 183 731 301 ..
    //                    718 91 109 567 708 507 983 808 766 615 554 282 995 946 651 298;
    //                    //Constraint 2
    //                    509 883 229 569 706 639 114 727 491 481 681 948 687 941 ..
    //                    350 253 573 40 124 384 660 951 739 329 146 593 658 816 ..
    //                    638 717 779 289 430 851 937 289 159 260 930 248 656 833 ..
    //                    892 60 278 741 297 967 86 249 354 614 836 290 893 857 ..
    //                    158 869 206 504 799 758 431 580 780 788 583 641 32 653 ..
    //                    252 709 129 368 440 314 287 854 460 594 512 239 719 751 ..
    //                    708 670 269 832 137 356 960 651 398 893 407 477 552 805 881 850;
    //                    //Constraint 3
    //                    806 361 199 781 596 669 957 358 259 888 319 751 275 177 ..
    //                    883 749 229 265 282 694 819 77 190 551 140 442 867 283 ..
    //                    137 359 445 58 440 192 485 744 844 969 50 833 57 877 ..
    //                    482 732 968 113 486 710 439 747 174 260 877 474 841 422 ..
    //                    280 684 330 910 791 322 404 403 519 148 948 414 894 147 ..
    //                    73 297 97 651 380 67 582 973 143 732 624 518 847 113 ..
    //                    382 97 905 398 859 4 142 110 11 213 398 173 106 331 254 447 ;
    //                    //Constraint 4
    //                    404 197 817 1000 44 307 39 659 46 334 448 599 931 776 ..
    //                    263 980 807 378 278 841 700 210 542 636 388 129 203 110 ..
    //                    817 502 657 804 662 989 585 645 113 436 610 948 919 115 ..
    //                    967 13 445 449 740 592 327 167 368 335 179 909 825 614 ..
    //                    987 350 179 415 821 525 774 283 427 275 659 392 73 896 ..
    //                    68 982 697 421 246 672 649 731 191 514 983 886 95 846 ..
    //                    689 206 417 14 735 267 822 977 302 687 118 990 323 993 525 322;
    //                    //Constrain 5
    //                    475 36 287 577 45 700 803 654 196 844 657 387 518 143 ..
    //                    515 335 942 701 332 803 265 922 908 139 995 845 487 100 ..
    //                    447 653 649 738 424 475 425 926 795 47 136 801 904 740 ..
    //                    768 460 76 660 500 915 897 25 716 557 72 696 653 933 ..
    //                    420 582 810 861 758 647 237 631 271 91 75 756 409 440 ..
    //                    483 336 765 637 981 980 202 35 594 689 602 76 767 693 ..
    //                    893 160 785 311 417 748 375 362 617 553 474 915 457 261 350 635 ;
    //     ];
    //    nbCon = size(conMatrix,1)
    //    nbVar = size(conMatrix,2)
    //    // Lower Bound of variables
    //    lb = repmat(0,nbVar,1)
    //    // Upper Bound of variables
    //    ub = repmat(1,nbVar,1)
    //    // Row Matrix for telling symphony that the is integer or not
    //    isInt = repmat(%t,1,nbVar)
    //    // Lower Bound of constrains
    //    conLB=repmat(0,nbCon,1);
    //    // Upper Bound of constraints
    //    conUB=[11927 13727 11551 13056 13460 ]';
    //    options = list("time_limit", 25);
    //    // The expected solution :
    //    // Output variables
    //    xopt = [0 1 1 0 0 1 0 1 0 1 0 0 0 0 0 0 0 1 0 0 0 0 1 0 1 1 0 1 1 0 1 .. 
    //            0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 1 1 0 0 1 0 ..
    //            0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 0 0 1 1 0 0 0 0 0 1 1 0 0 1 0 0 1 0]
    //    // Optimal value
    //    fopt = [ 24381 ]
    //    // Calling Symphony
    //    [x,f,status,output] = symphony(nbVar,nbCon,p,isInt,lb,ub,conMatrix,conLB,conUB,-1,options)
    //
    // Authors
    // Keyur Joshi, Saikiran, Iswarya, Harpreet Singh
    
//To check the number of input and output argument
   [lhs , rhs] = argn();
	
//To check the number of argument given by user
   if ( rhs < 9 | rhs > 11 ) then
    errmsg = msprintf(gettext("%s: Unexpected number of input arguments : %d provided while should be in the set [9 10 11]"), "Symphony", rhs);
    error(errmsg)
   end
   
   nbVar = varargin(1);
   nbCon = varargin(2);
   objCoef = varargin(3);
   isInt = varargin(4);
   LB = varargin(5);
   UB = varargin(6);
   conMatrix = varargin(7);
   conLB = varargin(8);
   conUB = varargin(9);
   
   if ( rhs<10 ) then
      objSense = 1;
   else
      objSense = varargin(10);
   end
   
   if (rhs<11|size(varargin(11))==0) then
      options = list();
   else
      options = varargin(11);
   end

// Check if the user gives row vector 
// and Changing it to a column matrix

   if (size(isInt,2)== [nbVar]) then
	isInt = isInt';
   end

   if (size(LB,2)== [nbVar]) then
	LB = LB';
   end

   if (size(UB,2)== [nbVar]) then
	UB = UB';
   end

   if (size(conLB,2)== [nbVar]) then
	conLB = conLB';
   end

   if (size(conUB,2)== [nbVar]) then
	conUB = conUB';
   end


   if (size(objCoef,2)~=1) then
	errmsg = msprintf(gettext("%s: Objective Coefficients should be a column matrix"), "Symphony");
	error(errmsg);
   end

   if (size(objCoef,1)~=nbVar) then
	errmsg = msprintf(gettext("%s: Number of variables in Objective Coefficients is not equal to number of variables given"), "Symphony");
	error(errmsg);
   end

   //Check the size of isInt which should equal to the number of variables
   if(size(isInt,1)~=nbVar) then
	errmsg = msprintf(gettext("%s: The size of isInt is not equal to the number of variables"), "Symphony");
	error(errmsg);
   end

   //Check the size of lower bound of inequality constraint which should equal to the number of constraints
   if ( size(conLB,1) ~= nbCon) then
      errmsg = msprintf(gettext("%s: The Lower Bound of constraint is not equal to the number of constraint"), "Symphony");
      error(errmsg);
   end

   //Check the size of lower bound of inequality constraint which should equal to the number of constraints
   if ( size(conUB,1) ~= nbCon) then
      errmsg = msprintf(gettext("%s: The Upper Bound of constraint is not equal to the number of constraint"), "Symphony");
      error(errmsg);
   end

   //Check the row of constraint which should equal to the number of constraints
   if ( size(conMatrix,1) ~= nbCon) then
      errmsg = msprintf(gettext("%s: The number of rows in constraint should be equal to the number of constraints"), "Symphony");
      error(errmsg);
   end

   //Check the column of constraint which should equal to the number of variables
   if ( size(conMatrix,2) ~= nbVar) then
      errmsg = msprintf(gettext("%s: The number of columns in constraint should equal to the number of variables"), "Symphony");
      error(errmsg);
   end

   //Check the size of Lower Bound which should equal to the number of variables
   if ( size(LB,1) ~= nbVar) then
      errmsg = msprintf(gettext("%s: The Lower Bound is not equal to the number of variables"), "Symphony");
      error(errmsg);
   end

   //Check the size of Upper Bound which should equal to the number of variables
   if ( size(UB,1) ~= nbVar) then
      errmsg = msprintf(gettext("%s: The Upper Bound is not equal to the number of variables"), "Symphony");
      error(errmsg);
   end
   
   if (type(options) ~= 15) then
      errmsg = msprintf(gettext("%s: Options should be a list "), "Symphony");
      error(errmsg);
   end
   
   if (modulo(size(options),2)) then
	errmsg = msprintf(gettext("%s: Size of parameters should be even"), "Symphony");
	error(errmsg);
   end

   LB = LB';
   UB = UB';
   isInt = isInt';
   objCoef = objCoef';

   [xopt,fopt,status,output] = symphony_call(nbVar,nbCon,objCoef,isInt,LB,UB,conMatrix,conLB,conUB,objSense,options);

endfunction