qrem.common.external.ncpol2sdpa.picos_utils

The module contains helper functions to work with PICOS.

Created on Wed Dec 10 18:33:34 2014

@author: Peter Wittek

Module Contents

Functions

solve_with_cvxopt(sdp[, solverparameters])

Helper function to convert the SDP problem to PICOS

convert_to_picos(sdp[, duplicate_moment_matrix])

Convert an SDP relaxation to a PICOS problem such that the exported
qrem.common.external.ncpol2sdpa.picos_utils.solve_with_cvxopt(sdp, solverparameters=None)

Helper function to convert the SDP problem to PICOS and call CVXOPT solver, and parse the output.

Parameters:

sdp (ncpol2sdpa.sdp.) – The SDP relaxation to be solved.

qrem.common.external.ncpol2sdpa.picos_utils.convert_to_picos(sdp, duplicate_moment_matrix=False)

Convert an SDP relaxation to a PICOS problem such that the exported .dat-s file is extremely sparse, there is not penalty imposed in terms of SDP variables or number of constraints. This conversion can be used for imposing extra constraints on the moment matrix, such as partial transpose.

Parameters:

  • sdp (ncpol2sdpa.sdp.) – The SDP relaxation to convert.

  • duplicate_moment_matrix (bool.) – Optional parameter to add an unconstrained moment matrix to the problem with the same structure as the moment matrix with the PSD constraint.

Returns:

picos.Problem.