Examples with GRBQuadExpr gurobi.GRBQuadExpr used on opensource projects

Example 1 with GRBQuadExpr

use of gurobi.GRBQuadExpr in project chordatlas by twak.

the class GurobiSkelSolver method buildProblem.

public void buildProblem() throws GRBException {
    model = new GRBModel(new GRBEnv(Tweed.SCRATCH + System.currentTimeMillis() + ".log"));
    target = new GRBQuadExpr();
    edgeInfo = new HashMap<>();
    faceInfo = new HashMap<>();
    buildColouringProblem();
    buildIsEdge();
    buildBadGeom(false);
    if (globalProfs != null)
        buildProfiles();
    if (minis != null && !minis.isEmpty())
        buildMini();
    for (HalfEdge he : edges) {
        target.addTerm(20 * he.length(), edgeInfo.get(he).edgeNoProfile);
        target.addTerm(40 * he.length(), edgeInfo.get(he).profileNoEdge);
    }
    // target.addTerm( 50 * he.length(), edgeInfo.get(he).isEdge );
    double isEdgeHeight = 0, isNotEdgeHeight = 0;
    for (HalfEdge e : edges) {
        double cost;
        if (e.over != null) {
            cost = e.length() * Math.abs(((SuperFace) e.face).height - ((SuperFace) e.over.face).height);
            isEdgeHeight += cost;
            isNotEdgeHeight += cost;
            // target.addTerm (      cost, edgeInfo.get(e).isNotEdge );
            target.addTerm(-4 * cost, edgeInfo.get(e).isEdge);
        }
    }
    print("is not edge height penalty " + isNotEdgeHeight + " (" + (isNotEdgeHeight / faceInfo.size()) + ")");
    print("is edge height penalty " + isEdgeHeight);
    model.setObjective(target, GRB.MINIMIZE);
}

Example 2 with GRBQuadExpr

use of gurobi.GRBQuadExpr in project chordatlas by twak.

the class SliceSolver method sliceOptimize.

public static int[] sliceOptimize(int numSlices, double[][] data, double[][] alignment) {
    try {
        GRBEnv env = new GRBEnv("mip1.log");
        GRBModel model = new GRBModel(env);
        GRBVar[][] xij = new GRBVar[numSlices][numSlices];
        for (int i = 0; i < numSlices; i++) for (int j = 0; j < numSlices; j++) xij[i][j] = model.addVar(0.0, 1.0, 1.0, GRB.BINARY, "x" + i + "_" + j);
        // overlap term n^2 terms
        for (int i = 0; i < numSlices; i++) {
            GRBLinExpr expr = new GRBLinExpr();
            for (int j = 0; j < numSlices; j++) expr.addTerm(1, xij[i][j]);
            model.addConstr(expr, GRB.EQUAL, 1, "overlap_" + i);
        }
        // for ( int i = 0; i < numSlices-1; i++ ) {
        // for ( int j = 0; j < numSlices; j++ ) {
        // GRBLinExpr expr = new GRBLinExpr();
        // expr.addTerm(  1, xij[ i   ] [ j ] );
        // expr.addTerm( -1, xij[ i+1 ] [ j ] );
        // model.addConstr( expr, GRB.EQUAL, 0, "super_adjacency" + j );
        // }
        // }
        // data fitting term n^2 terms
        GRBQuadExpr target = new GRBQuadExpr();
        for (int i = 0; i < numSlices; i++) {
            for (int j = 0; j < numSlices; j++) {
                if (data[i][j] != Double.MAX_VALUE)
                    target.addTerm(data[i][j] * 30, xij[i][j]);
                else
                    target.addTerm(1e3, xij[i][j]);
            }
        }
        // neighbour alignment n^3 quadratic terms
        for (int i = 0; i < numSlices - 1; i++) for (int ja = 0; ja < numSlices; ja++) for (int jb = 0; jb < numSlices; jb++) target.addTerm(alignment[ja][jb] == Double.MAX_VALUE ? 1e2 : alignment[ja][jb], xij[i][ja], xij[i + 1][jb]);
        model.setObjective(target, GRB.MINIMIZE);
        model.getEnv().set(GRB.DoubleParam.TimeLimit, 10.0);
        model.optimize();
        // xij[0][0].set( DoubleAttr.X, 1 );
        // target.getValue();
        System.out.println("Obj: " + model.get(GRB.DoubleAttr.ObjVal));
        int[] out = new int[numSlices];
        for (int i = 0; i < numSlices; i++) {
            System.out.print("i: " + i + " ");
            for (int j = 0; j < numSlices; j++) {
                System.out.print(xij[i][j].get(GRB.DoubleAttr.X) + " ");
                if (xij[i][j].get(GRB.DoubleAttr.X) == 1)
                    out[i] = j;
            }
            System.out.println();
        }
        // Dispose of model and environment
        model.dispose();
        env.dispose();
        return out;
    } catch (GRBException e) {
        System.out.println("Error code: " + e.getErrorCode() + ". " + e.getMessage());
        e.printStackTrace();
    }
    return null;
}