update requirements

We plan a release no earlier than September 2020, which means that
we target Debian buster and Ubuntu focal when determining package
versions

INSTALL.rst

@@ -29,10 +29,9 @@ Prerequisites
 =============
 
 Building Kwant requires
- * `Python <https://www.python.org/>`_ 3.6 or above (Kwant 1.1 is the last
-   version to support Python 2),
- * `NumPy <https://numpy.org/>`_ 1.13.3 or newer,
- * `SciPy <https://www.scipy.org/>`_ 0.19.1 or newer,
+ * `Python <https://www.python.org/>`_ 3.7 or above,
+ * `NumPy <https://numpy.org/>`_ 1.16.2 or newer,
+ * `SciPy <https://www.scipy.org/>`_ 1.1.0 or newer,
  * `LAPACK <https://netlib.org/lapack/>`_ and `BLAS <https://netlib.org/blas/>`_,
    (For best performance we recommend the free `OpenBLAS
    <https://www.openblas.net/>`_ or the nonfree `MKL
@@ -43,9 +42,10 @@ a NumPy-like Python package optimized for very small arrays,
    C++.
 
 The following software is highly recommended though not strictly required:
- * `matplotlib <https://matplotlib.org/>`_ 2.1.1 or newer, for the module `kwant.plotter` and the tutorial,
- * `SymPy <https://sympy.org/>`_ 1.1.1 or newer, for the subpackage `kwant.continuum`.
- * `Qsymm <https://pypi.org/project/qsymm/>`_ 1.2.6 or newer, for the subpackage `kwant.qsymm`.
+ * `matplotlib <https://matplotlib.org/>`_ 3.0.2 or newer, for the module `kwant.plotter` and the tutorial,
+ * `plotly <https://plotly.com/>`_ 3.6.1 or newer, for the module `kwant.plotter` and the tutorial,
+ * `SymPy <https://sympy.org/>`_ 1.3.0 or newer, for the subpackage `kwant.continuum`.
+ * `Qsymm <https://pypi.org/project/qsymm/>`_ 1.3.0 or newer, for the subpackage `kwant.qsymm`.
  * `MUMPS <https://graal.ens-lyon.fr/MUMPS/>`_, a sparse linear algebra library
    that will in many cases speed up Kwant several times and reduce the memory
    footprint.  (Kwant uses only the sequential, single core version

docker/Dockerfile.debian

-FROM debian:latest
+FROM debian:buster
 
 ENV LANG C.UTF-8
 ENV LC_ALL C.UTF-8
@@ -24,7 +24,7 @@ RUN echo "deb https://downloads.kwant-project.org/debian/ stable main" >> /etc/a
 
 ### install optional dependencies not available from the Debian repositories
 RUN pip3 install \
-    qsymm==1.2.6
+    qsymm==1.3.0
 
 ### install build and testing dependencies
 RUN pip3 install \

docker/Dockerfile.ubuntu

-FROM ubuntu:18.04
+FROM ubuntu:20.04
 
 ENV LANG C.UTF-8
 ENV LC_ALL C.UTF-8
@@ -22,7 +22,7 @@ RUN apt-add-repository -s ppa:kwant-project/ppa && \
 
 ### install optional dependencies not available from the Debian repositories
 RUN pip3 install \
-    qsymm==1.2.6
+    qsymm==1.3.0
 
 ### install build and testing dependencies
 RUN pip3 install \

docker/kwant-latest.yml

@@ -2,14 +2,14 @@ name: kwant-latest
 channels:
     - conda-forge
 dependencies:
-    - python=3.6
+    - python=3.9
     - numpy
     - scipy
     - tinyarray
     - sympy
-    - matplotlib
-    - qsymm
+    - matplotlib-base
     - plotly
+    - qsymm
     # Linear algebra libraraies
     - mumps-seq
     - mumps-include
@@ -30,6 +30,3 @@ dependencies:
     - numpydoc
     - requests
     - jupyter_sphinx
-    - pip
-    - pip:
-        - sphinxcontrib-svg2pdfconverter

docker/kwant-stable-no-extras.yml

@@ -2,10 +2,10 @@ name: kwant-stable-no-extras
 channels:
     - conda-forge
 dependencies:
-    - python=3.6
-    - numpy=1.13.1
-    - scipy=0.19.1
-    - tinyarray=1.2.0
+    - python=3.7
+    - numpy=1.16.2
+    - scipy=1.1.0
+    - tinyarray=1.2
     # Linear algebra libraraies
     - blas #=1.1 openblas
     - openblas #=0.2.20

docker/kwant-stable.yml

@@ -2,14 +2,14 @@ name: kwant-stable
 channels:
     - conda-forge
 dependencies:
-    - python=3.6
-    - numpy=1.13.3
-    - scipy=0.19.1
-    - tinyarray=1.2.0
-    - sympy=1.1.1
-    - matplotlib=2.1.1
-    - qsymm=1.2.6
-    - plotly=2.2.2
+    - python=3.7
+    - numpy=1.16.2
+    - scipy=1.1.0
+    - tinyarray=1.2
+    - sympy=1.3.0
+    - matplotlib-base=3.0.2
+    - plotly=3.6.1
+    - qsymm=1.3.0
     # Linear algebra libraraies
     - mumps-seq
     - mumps-include

setup.py

@@ -593,16 +593,16 @@ def main():
                     'build_ext': build_ext,
                     'test': test},
           ext_modules=exts,
-          python_requires='>=3.6',
-          install_requires=['numpy >= 1.13.3', 'scipy >= 0.19.1',
+          python_requires='>=3.7',
+          # The oldest versions between: Debian stable, Ubuntu LTS
+          install_requires=['numpy >= 1.16.2', 'scipy >= 1.1.0',
                             'tinyarray >= 1.2'],
           extras_require={
-              # The oldest versions between: Debian stable, Ubuntu LTS
-              'plotting': ['matplotlib >= 2.1.1',
-                           'plotly >= 2.2.2'],
-              'continuum': 'sympy >= 1.1.1',
+              'plotting': ['matplotlib >= 3.0.2',
+                           'plotly >= 3.6.1'],
+              'continuum': 'sympy >= 1.3.0',
               # qsymm is only packaged on PyPI
-              'qsymm': 'qsymm >= 1.2.6',
+              'qsymm': 'qsymm >= 1.3.0',
           },
           classifiers=[c.strip() for c in classifiers.split('\n')])