João Patrício

Fortran subroutines for network flow optimization using an interior point algorithm

  • Joaquim J. Júdice
  • João Patrício
  • Luis F. Portugal
  • Mauricio G.C. Resende
  • Geraldo Veiga
    • Categories Network Optimization, Optimization Software and Modeling Systems Tags , ,

    We describe FORTRAN subroutines for network flow optimization using an interior point network flow algorithm. We provide FORTRAN and C language drivers, as well as C language functions that, together with the subroutines, make up PDNET (Portugal, Resende, Veiga, and Júdice, 2000). The algorithm is described in detail and its implementation is outlined. Usage of … Read more

    A study of preconditioners for network interior point methods

  • Joaquim J. Júdice
  • João Patrício
  • Luis F. Portugal
  • Mauricio G.C. Resende
  • Geraldo Veiga
    • Categories Network Optimization Tags , , , ,

    We study and compare preconditioners available for network interior point methods. We derive upper bounds for the condition number of the preconditioned matrices used in the solution of systems of linear equations defining the algorithm search directions. The preconditioners are tested using PDNET, a state-of-the-art interior point code for the minimum cost network flow problem. … Read more