diff --git a/doc/source/pre/whatsnew/1.4.rst b/doc/source/pre/whatsnew/1.4.rst
index 0efda7e2d05d814838a4a26f2caf44a3246e4373..945a4bfb374ae015dd3a2daab4613ba23348240e 100644
--- a/doc/source/pre/whatsnew/1.4.rst
+++ b/doc/source/pre/whatsnew/1.4.rst
@@ -5,78 +5,64 @@ This article explains the user-visible changes in Kwant 1.4.0. Subsequently,
the user-visible changes for each maintenance release of the 1.4.x series are
listed (if there were any).
-Value functions may no longer take unnamed arguments
-----------------------------------------------------
-The system parameter (``args`` and ``params``) handling of Kwant has been
-rewritten following the principle that each value function must take a clearly
-specified set of named parameters. This allows to make the parameter handling
-less error-prone (as explained in the following section) and faster. For this
-reason, value functions may no longer accept ``*args`` or ``**kwargs``.
+Summary: release highlights
+---------------------------
+* Adding magnetic field to systems, even in complicated cases, is now specially
+ :ref:`supported <whatsnew14-magnetic>`.
+* The :ref:`KPM module can now calculate conductivities
+ <whatsnew14-kpm-conductivity>`.
+* The `Qsymm library <https://gitlab.kwant-project.org/qt/qsymm>`_ for
+ Hamiltonian symmetry analysis has been :ref:`integrated <whatsnew14-qsymm>`.
+* The handling of system parameters has been :ref:`improved
+ <whatsnew14-parameters>` and optimized.
+* Plotting has been improved, most notably through the addition of a :ref:`routine
+ that plots densities with interpolation <whatsnew14-density-plots>`.
+* :ref:`Installing Kwant on Windows <whatsnew14-windows>` is now much easier
+ thanks to Conda packages.
+
+Backwards-incompatible changes:
+
+* `Value functions may no longer take unnamed arguments`_.
+* `Value functions may no longer have default values for parameters`_.
+
+.. _whatsnew14-magnetic:
-If you are using such functions, we recommend that you replace them by named
-parameters.
-
-Value functions may no longer have default values for parameters
-----------------------------------------------------------------
-Using value functions with default values for parameters can be
-problematic, especially when re-using value functions between simulations.
-When parameters have default values it is easy to forget that such a
-parameter exists at all, because it is not necessary to provide them explicitly
-to functions that use the Kwant system. This means that other value functions
-might be introduced that also depend on the same parameter,
-but in an inconsistent way (e.g. a parameter 'phi' that is a superconducting
-phase in one value function, but a peierls phase in another). This leads
-to bugs that are confusing and hard to track down.
-
-For this reason value functions may no longer have default values for paramters.
-Concretely this means that the following no longer works::
-
- syst = kwant.Builder()
-
- # Parameter 't' has a default value of 1
- def onsite(site, V, t=1):
- return V = 2 * t
+Automatic Peierls phase calculation
+-----------------------------------
+When defining systems with orbital magnetic fields it is often cumbersome to
+manually calculate the phases required by the Peierls substitution, and to
+ensure that the chosen gauge is consistent across the whole system
+(this is especially true for systems with leads that point in different
+directions). This release introduces `kwant.physics.magnetic_gauge`,
+which calculates the Peierls phases for you::
- def hopping(site_a, site_b, t=1):
- return -t
+ import numpy as np
+ import kwant
- syst[...] = onsite
- syst[...] = hopping
+ def hopping(a, b, t, peierls):
+ return -t * peierls(a, b)
- # Raises ValueError
+ syst = make_system(hopping)
+ lead = make_lead(hopping).substituted(peierls='peierls_lead')
+ syst.attach_lead(lead)
syst = syst.finalized()
-As a solution, simply remove the default values and always provide ``t``.
-To deal with many parameters, the following idiom may be useful::
-
- defaults = dict(a=0, b=1, c=2, d=3)
- ...
- smatrix = kwant.smatrix(syst, E, params=dict(defaults, d=4, e=5))
+ gauge = kwant.physics.magnetic_gauge(syst)
-Note that this allows to override defaults as well as to add additional
-parameters.
+ def B_syst(pos):
+ return np.exp(-np.sum(pos * pos))
-Installation on Microsoft Windows is available via Conda
---------------------------------------------------------
-Kwant is now packaged for the Conda package manager on Windows, and using
-Conda is the preferred method for installing Kwant on that platform.
-Please refer to the
-`installation section <https://kwant-project.org/install#microsoft-windows>`_
-of the Kwant website for details.
-Currently the MUMPS solver is not available for the Windows version of the
-Conda package; we hope to include MUMPS support in a later patch release.
+ # B_syst in scattering region, 0 in lead.
+ # Ensure that the fields match at the system/lead interface!
+ peierls_syst, peierls_lead = gauge(B_syst, 0)
-Minimum required versions for some dependencies have increased
---------------------------------------------------------------
-Kwant now requires at least the following versions:
+ params = dict(t=1, peierls=peierls_syst, peierls_lead=peierls_lead)
+ kwant.hamiltonian_submatrix(syst, params=params)
-+ Python 3.5
-+ numpy 0.11.0
-+ scipy 0.17.0
-+ matplotlib 1.5.1
+Note that the API for this functionality is provisional, and may be
+revised in a future version of Kwant.
-These versions (or newer) are available in the latest stable releases
-of Ubuntu and Debian GNU/Linux.
+.. _whatsnew14-kpm-conductivity:
Conductivity calculations using `kwant.kpm.conductivity`
--------------------------------------------------------
@@ -90,17 +76,7 @@ potentials at finite temperature::
conductivities = [sigma_xy(mu=mu, temperature=0.1)
for mu in np.linspace(0, 4)]
-`kwant.physics.Bands` can optionally return eigenvectors and velocities
------------------------------------------------------------------------
-`kwant.physics.Bands` now takes extra parameters that allow it to
-return the mode eigenvectors, and also the derivatives of the dispersion
-relation (up to second order) using the Hellman-Feynman relation::
-
- syst = make_system().finalized()
-
- bands = kwant.physics.Bands(syst)
- (energies, velocities, vectors) = bands(k=0, derivative_order=1,
- return_eigenvectors=True)
+.. _whatsnew14-qsymm:
Integration with Qsymm library
------------------------------
@@ -136,40 +112,7 @@ and vice versa, and for working with continuum Hamiltonians (such as would be us
This integration requires separately installing Qsymm, which is available on the
`Python Package Index <https://pypi.org/project/qsymm/>`_.
-Automatic Peierls phase calculation
------------------------------------
-When defining systems with orbital magnetic fields it is often cumbersome to
-manually calculate the phases required by the Peierls substitution, and to
-ensure that the chosen gauge is consistent across the whole system
-(this is especially true for systems with leads that point in different
-directions). This release introduces `kwant.physics.magnetic_gauge`,
-which calculates the Peierls phases for you::
-
- import numpy as np
- import kwant
-
- def hopping(a, b, t, peierls):
- return -t * peierls(a, b)
-
- syst = make_system(hopping)
- lead = make_lead(hopping).substituted(peierls='peierls_lead')
- syst.attach_lead(lead)
- syst = syst.finalized()
-
- gauge = kwant.physics.magnetic_gauge(syst)
-
- def B_syst(pos):
- return np.exp(-np.sum(pos * pos))
-
- # B_syst in scattering region, 0 in lead.
- # Ensure that the fields match at the system/lead interface!
- peierls_syst, peierls_lead = gauge(B_syst, 0)
-
- params = dict(t=1, peierls=peierls_syst, peierls_lead=peierls_lead)
- kwant.hamiltonian_submatrix(syst, params=params)
-
-Note that the API for this functionality is provisional, and may be
-revised in a future version of Kwant.
+.. _whatsnew14-parameters:
System parameter substitution
-----------------------------
@@ -248,27 +191,7 @@ a dictionary using ``params``::
Providing ``args`` will be removed in a future Kwant version.
-Finalized Builders keep track of which sites were added when attaching leads
-----------------------------------------------------------------------------
-When attaching leads to an irregularly shaped scattering region, Kwant adds
-sites in order to make the interface with the leads "smooth". Previously,
-the information of which sites were added was not inspectable after finalization.
-Now the sites that were added from each lead are available in the ``lead_paddings``
-attribute. See the documentation for `~kwant.builder.FiniteSystem` for details.
-
-`kwant.continuum.discretize` can be used with rectangular lattices
-------------------------------------------------------------------
-Previously the discretizer could only be used with lattices with the same
-lattice constant in all directions. Now it is possible to pass rectangular
-lattices to the discretizer::
-
- kwant.continuum.discretize(
- 'k_x**2 + k_y**2',
- grid=kwant.lattice.general([(1, 0), (0, 2]),
- )
-
-This is useful when you need a finer discretization step in some spatial
-directions, and a coarser one in others.
+.. _whatsnew14-density-plots:
Interpolated density plots
--------------------------
@@ -304,6 +227,115 @@ different families are plotted in different colors, which improves the
default plotting style. You can still customize the site coloring using
the ``site_color`` parameter, as before.
+`kwant.physics.Bands` can optionally return eigenvectors and velocities
+-----------------------------------------------------------------------
+`kwant.physics.Bands` now takes extra parameters that allow it to
+return the mode eigenvectors, and also the derivatives of the dispersion
+relation (up to second order) using the Hellman-Feynman relation::
+
+ syst = make_system().finalized()
+
+ bands = kwant.physics.Bands(syst)
+ (energies, velocities, vectors) = bands(k=0, derivative_order=1,
+ return_eigenvectors=True)
+
+Finalized Builders keep track of which sites were added when attaching leads
+----------------------------------------------------------------------------
+When attaching leads to an irregularly shaped scattering region, Kwant adds
+sites in order to make the interface with the leads "smooth". Previously,
+the information of which sites were added was not inspectable after finalization.
+Now the sites that were added from each lead are available in the ``lead_paddings``
+attribute. See the documentation for `~kwant.builder.FiniteSystem` for details.
+
+`kwant.continuum.discretize` can be used with rectangular lattices
+------------------------------------------------------------------
+Previously the discretizer could only be used with lattices with the same
+lattice constant in all directions. Now it is possible to pass rectangular
+lattices to the discretizer::
+
+ kwant.continuum.discretize(
+ 'k_x**2 + k_y**2',
+ grid=kwant.lattice.general([(1, 0), (0, 2]),
+ )
+
+This is useful when you need a finer discretization step in some spatial
+directions, and a coarser one in others.
+
+Value functions may no longer take unnamed arguments
+----------------------------------------------------
+The system parameter (``args`` and ``params``) handling of Kwant has been
+rewritten following the principle that each value function must take a clearly
+specified set of named parameters. This allows to make the parameter handling
+less error-prone (as explained in the following section) and faster. For this
+reason, value functions may no longer accept ``*args`` or ``**kwargs``.
+
+If you are using such functions, we recommend that you replace them by named
+parameters.
+
+Value functions may no longer have default values for parameters
+----------------------------------------------------------------
+Using value functions with default values for parameters can be
+problematic, especially when re-using value functions between simulations.
+When parameters have default values it is easy to forget that such a
+parameter exists at all, because it is not necessary to provide them explicitly
+to functions that use the Kwant system. This means that other value functions
+might be introduced that also depend on the same parameter,
+but in an inconsistent way (e.g. a parameter 'phi' that is a superconducting
+phase in one value function, but a peierls phase in another). This leads
+to bugs that are confusing and hard to track down.
+
+For this reason value functions may no longer have default values for paramters.
+Concretely this means that the following no longer works::
+
+ syst = kwant.Builder()
+
+ # Parameter 't' has a default value of 1
+ def onsite(site, V, t=1):
+ return V = 2 * t
+
+ def hopping(site_a, site_b, t=1):
+ return -t
+
+ syst[...] = onsite
+ syst[...] = hopping
+
+ # Raises ValueError
+ syst = syst.finalized()
+
+As a solution, simply remove the default values and always provide ``t``.
+To deal with many parameters, the following idiom may be useful::
+
+ defaults = dict(a=0, b=1, c=2, d=3)
+ ...
+ smatrix = kwant.smatrix(syst, E, params=dict(defaults, d=4, e=5))
+
+Note that this allows to override defaults as well as to add additional
+parameters.
+
+.. _whatsnew14-windows:
+
+Installation on Microsoft Windows is available via Conda
+--------------------------------------------------------
+Kwant is now packaged for the Conda package manager on Windows, and using
+Conda is the preferred method for installing Kwant on that platform.
+Please refer to the
+`installation section <https://kwant-project.org/install#microsoft-windows>`_
+of the Kwant website for details.
+Currently the MUMPS solver is not available for the Windows version of the
+Conda package; we hope to include MUMPS support in a later patch release.
+
+Minimum required versions for some dependencies have increased
+--------------------------------------------------------------
+Kwant now requires at least the following versions:
+
++ Python 3.5
++ numpy 0.11.0
++ scipy 0.17.0
++ matplotlib 1.5.1
+
+These versions (or newer) are available in the latest stable releases
+of Ubuntu and Debian GNU/Linux.
+
Changes in Kwant 1.4.1
----------------------
- The list of user-visible changes was rearranged to emphasize