cleaned up conventions

Author: zerothi

docs/math.rst docs/conventions.rstdocs/math.rst renamed to docs/conventions.rst

@@ -1,12 +1,36 @@
-.. _math_convention:
 
-Mathematical notation convention
-================================
+.. _conventions:
 
-In `sisl` we strive to make the documentation as consistent
-as possible.
-This should make reading different parts of the documentation
-simple to understand.
+Conventions in sisl
+===================
+
+sisl is a joint effort to enable easy usage of electronic structure
+concepts in a scientific setting. Ranging between introductory levels
+up to, and including, full scientific employees.
+
+There are certain conventions that we want to enforce in sisl, and
+we strive them as far as possible.
+
+
+
+.. _conventions.units:
+
+Units
+-----
+
+All units in sisl are standardized to:
+
+Length
+   All units internally and returned are in Angstrom.
+
+Energy
+   All units internally and returned are in electron volts.
+
+
+.. _convention.mathematics:
+
+Mathematical notation
+---------------------
 
 Here is a list of rules that sisl will strive to adhere to.
 If you find any inconsistencies in the documentation,

docs/index.rst

@@ -103,7 +103,7 @@ Since then it has expanded to accommodate a rich set of DFT code input/outputs.
    :maxdepth: 3
    :caption: Extras
 
-   math
+   conventions
    release
    other
    references

docs/quickstart/overview.rst

@@ -18,18 +18,6 @@ sisl is a Python package providing access to a large variety of things.
   exploration of calculations
 
 
-Units
------
-
-sisl assumes the user is careful in using consistent units.
-
-The internal units in sisl are:
-
-* Ang (Angstrom)
-* eV (electron volt)
-
-If you wish to introduce a specific unit, and its default, please open an `issue`_.
-
 
 Data structures
 ---------------

src/sisl/io/tbtrans/tbt.py

@@ -117,7 +117,7 @@ class tbtncSileTBtrans(_devncSileTBtrans):
     are in fortran indexing (1-based), everything is returned as Python indexing (0-based)
     when using Python scripts.
 
-    The mathematical notation described :ref:`here <math_convention>`
+    The mathematical notation described :ref:`here <convention.mathematics>`
     will be used throughout.
 
     A word on DOS normalization:

src/sisl/physics/densitymatrix.py

@@ -34,7 +34,7 @@ class _densitymatrix(SparseOrbitalBZSpin):
     def mulliken(self, projection: Literal["orbital", "atom"] = "orbital"):
         r""" Calculate Mulliken charges from the density matrix
 
-        See :ref:`here <math_convention>` for details on the mathematical notation.
+        See :ref:`here <convention.mathematics>` for details on the mathematical notation.
         Matrices :math:`\boldsymbol\rho` and :math:`\mathbf S` are density
         and overlap matrices, respectively.