Changelog

1.0.2 - 2020-09-27 Bug Fix

Fixed

1.0.1 - 2020-09-25 Bug Fix and Minor Feature Release

Added

  • All walk sub-classes will now initialise \(\rho(0)\) as a maximally mixed state on passing ‘mixed’ to initial_state().

Fixed

  • Fixed incorrect superoperator generation when using the GQSW class which occurred when a global Lindblad operator had an empty row aligning with the first row of the local partition of the \(L^TL^* \otimes I_N\) term in \(\tilde{\mathcal{L}}\).
  • Edited the ‘Theory’ and ‘Package Overview’ sections of the package documentation to be in line with reviewer comments on the corresponding journal article.

Changed

  • Changed plot sizes and plot text sizes in response to reviewer feedback.
  • Enabled plot legends in desktop benchmarks output.
  • Desktop accuracy benchmarks now consider only \(\mathrm{max}(|\Delta\rho(t)|)\).

1.0.0 - 2020-07-01 Feature Release

This is a major revision of QSW_MPI. The focus of this release is the expansion of the simulation capabilities of QSW_MPI while focussing the scope of the package through the removal of features which are better supported through pre-existing alternatives (specifically file I/O and visualisation).

Added

  • Generalised support for quantum stochastic walks, including the non-moralising quantum stochastic walk through the LQSW and GQSW classes.
  • Experimental support for sparse systems following the Gorini–Kossakowski–Sudarshan–Lindblad equation in its diagonalised form through the GKSL class.
  • Support for MPI-enabled parallel output to HDF5 using H5Py via the non-user accessible module parallel_io.
  • Additional operator types including the canonical Markov chain transition matrix, and those required for the demoralisation correction scheme.

Changed

  • All simulation types are now subclasses a generalised walk class. This breaks compatibility with version 0.0.1.
  • step() and series() have been simplified, gathering of simulation results, or saving of the simulation results is now carried out through the gather_result(), gather_populations(), save_result() or save_populations().

Removed

  • Removed visualisation module plot. For basic visualisation, direct use of Matplotlib and Networkx is recommended.
  • Removed dedicated I/O module io. For HDF5 file operations, direct use of H5Py is recommended.

0.0.1 - 2020-03-05 Initial Release

Note

This version supports only quantum stochastic walk simulation with locally interacting Lindblad operators.