From 68d4965495a8d580b1181d99efe706a0f366eba6 Mon Sep 17 00:00:00 2001 From: Christoph Groth <christoph.groth@cea.fr> Date: Wed, 26 Sep 2018 11:40:13 +0200 Subject: [PATCH] reorder 1.4 whatsnew by decreasing importance --- doc/source/pre/whatsnew/1.4.rst | 84 ++++++++++++++++----------------- 1 file changed, 42 insertions(+), 42 deletions(-) diff --git a/doc/source/pre/whatsnew/1.4.rst b/doc/source/pre/whatsnew/1.4.rst index 375a2024..e7674772 100644 --- a/doc/source/pre/whatsnew/1.4.rst +++ b/doc/source/pre/whatsnew/1.4.rst @@ -6,48 +6,6 @@ See also the `full list of changes up to the most recent bugfix release of the 1.4 series <https://gitlab.kwant-project.org/kwant/kwant/compare/v1.4.0...latest-1.4>`_. -Configurable maximum velocity in stream plots ---------------------------------------------- -The function `~kwant.plotter.streamplot` has got a new option ``vmax``. Note -that this option is not available in `~kwant.plotter.current`. In order to use -it, one has to call ``streamplot`` directly as shown in the docstring of -``current``. - -Improved heuristic for colorscale limits in `kwant.plotter.map` ---------------------------------------------------------------- -Previously `~kwant.plotter.map` would set the limits for the color scale -to the extrema of the data being plotted when ``vmin`` and ``vmax`` were -not provided. This is the behaviour of ``matplotlib.imshow``. When the data -to be plotted has very sharp and high peaks this would mean that most of the -data would appear near the bottom of the color scale, and all of the features -would be washed out by the presence of the peak. Now `~kwant.plotter.map` -employs a heuristic for setting the colorscale when there are outliers, -and will emit a warning when this is detected. - -System parameter substitution ------------------------------ -After the introduction of ``Builder.fill`` it has become possible to construct -Kwant systems by first creating a "model" system with high symmetry and then -filling a lower symmetry system with this model. Often, however, one wants -to use different parameter values in different parts of a system. In -previous versions of Kwant this was difficult to achieve. - -Builders now have a method ``substitute`` that makes it easy to substitute -different names for parameters. For example if a builder ``model`` -has a parameter ``V``, and one wishes to have different values for ``V`` in -the scattering region and leads, one could do the following:: - - syst = kwant.Builder() - syst.fill(model.substitute(V='V_dot', ...)) - - lead = kwant.Builder() - lead.fill(model.substitute(V='V_lead'), ...) - - syst.attach_lead(lead) - fsyst = syst.finalized() - - kwant.smatrix(syst, params=dict(V_dot=0, V_lead=1)) - Value functions no longer accept default values for parameters -------------------------------------------------------------- Using value functions with default values for parameters can be @@ -77,6 +35,30 @@ Concretely, the above means that the following no longer works:: # Raises ValueError syst = syst.finalized() +System parameter substitution +----------------------------- +After the introduction of ``Builder.fill`` it has become possible to construct +Kwant systems by first creating a "model" system with high symmetry and then +filling a lower symmetry system with this model. Often, however, one wants +to use different parameter values in different parts of a system. In +previous versions of Kwant this was difficult to achieve. + +Builders now have a method ``substitute`` that makes it easy to substitute +different names for parameters. For example if a builder ``model`` +has a parameter ``V``, and one wishes to have different values for ``V`` in +the scattering region and leads, one could do the following:: + + syst = kwant.Builder() + syst.fill(model.substitute(V='V_dot', ...)) + + lead = kwant.Builder() + lead.fill(model.substitute(V='V_lead'), ...) + + syst.attach_lead(lead) + fsyst = syst.finalized() + + kwant.smatrix(syst, params=dict(V_dot=0, V_lead=1)) + Interpolated density plots -------------------------- A new function `~kwant.plotter.density` has been added that can be used to @@ -86,6 +68,13 @@ in realspace. The output of `~kwant.plotter.density` can be more informative that `~kwant.plotter.map` when plotting systems with many sites, where it is not important to see the individual contribution from each site. +Configurable maximum velocity in stream plots +--------------------------------------------- +The function `~kwant.plotter.streamplot` has got a new option ``vmax``. Note +that this option is not available in `~kwant.plotter.current`. In order to use +it, one has to call ``streamplot`` directly as shown in the docstring of +``current``. + kwant.continuum.discretize can be used with rectangular lattices ---------------------------------------------------------------- Previously the discretizer could only be used with lattices with the same @@ -99,3 +88,14 @@ lattices to the discretizer:: This is useful when you need a finer discretization step in some spatial directions, and a coarser one in others. + +Improved heuristic for colorscale limits in `kwant.plotter.map` +--------------------------------------------------------------- +Previously `~kwant.plotter.map` would set the limits for the color scale +to the extrema of the data being plotted when ``vmin`` and ``vmax`` were +not provided. This is the behaviour of ``matplotlib.imshow``. When the data +to be plotted has very sharp and high peaks this would mean that most of the +data would appear near the bottom of the color scale, and all of the features +would be washed out by the presence of the peak. Now `~kwant.plotter.map` +employs a heuristic for setting the colorscale when there are outliers, +and will emit a warning when this is detected. -- GitLab