Sagnik Basumallik

Gurobi-versary
Investigator
Conversationalist
  • Total activity 37
  • Last activity
  • Member since
  • Following 0 users
  • Followed by 0 users
  • Votes 4
  • Subscriptions 12

Activity overview

Latest activity by Sagnik Basumallik
  • Sagnik Basumallik commented,

    Hi Jaromił, I tried two different ways: 1. First, I tried writing $\textrm{trace}A'BA$ as $\textrm{trace}BAA'$ and then computing $\textrm{trace}BM$ where $M=AA'$ computed offline. This still took ...

  • Sagnik Basumallik commented,

    Hi Jaromił, Thank you for your help. I think there was one thing that I missed mentioning is that in the expression trace(A^TBA), matrix B is a matrix with Gurobi variables on the diagonal. Ex, B =...

  • Sagnik Basumallik created a post,

    Error when using Sparse matrix with Gurobi variables

    Answered

    Hi, I have a dense matrix H which I have transformed into a sparse matrix. from scipy import sparsesH = sparse.csr_matrix(H) I have a D matrix which is an identity matrix with Gurobi variables in t...

  • Sagnik Basumallik created a post,

    Creating model takes too much time when big matrices are used

    Answered

    Hi All I have a problem that minimizes the following: minimize trace(A^TBA) where the matrices A and B have the following dimension A = (3038 x 2000) B = (3038 x 3038) I write the objective functio...

  • Sagnik Basumallik created a post,

    Duality of MILP

    Answered

    I am trying to understand if Gurobi derives lower bounds on the optimal solution value of a MILP problem using dual functions when Branch-and-Cut is used.  If yes, is there a way to access the dual...

  • Sagnik Basumallik created a post,

    Tolerances for Floating Point numbers under Integer Relaxation

    Answered

    I am trying to relax integer variables such that the resulting problem is linear. To do this, I am using a iterative weighted approach. The intermediate solutions I obtain (say after 6 iterations) ...

  • Sagnik Basumallik created a post,

    How does Gurobi handle binary variables in Mixed Integer (Binary) Linear Program?

    I have a Mixed Integer (Binary) Linear Program with the following variables. x = m.addVars(nodes, area,vtype=GRB.BINARY, name="x") w = m.addVars(arcs,area, vtype=GRB.BINARY, name="w") z = m.addVars...

  • Sagnik Basumallik commented,

    Thank you Dr. Yuriy Zinchenko. I did figure this out later after reading "multi-objective optimization in theory and practice: classical methods 1"

  • Sagnik Basumallik commented,

    Let us say we have the following: m.setObjective(w1*obj1+w2*obj2+w3*obj3) or m.setObjectiveN(obj1, index = 1, priority = 4, abstol=5.0) m.setObjectiveN(obj2, index = 2, priority = 3, abstol=4.0) m....

  • Sagnik Basumallik created a post,

    How do I obtain Pareto optimal solutions in Gurobi?

    Answered

    Currently, I am solving a MOOP in Gurobi. The first way is the linearly blended method. m.setObjective(obj1+obj2+obj3) Next, I have re-write n-1 objectives using the ε-constraint method, m.addConst...