Rename tau to kinetic energy (#173)

* rename tau to kinetic_energy
* fix tests after renaming

src/py4vasp/calculation/_density.py

@@ -84,7 +84,7 @@ def __str__(self):
         _raise_error_if_no_data(self._raw_data.charge)
         grid = self._raw_data.charge.shape[1:]
         topology = calculation.topology.from_data(self._raw_data.structure.topology)
-        if self._selection == "tau":
+        if self._selection == "kinetic_energy":
             name = "Kinetic energy"
         elif self.is_nonpolarized():
             name = "Nonpolarized"
@@ -114,15 +114,15 @@ def selections(self):
         the 0-th component.
 
         To nest density and component, please use parentheses, e.g. ``charge(1, 2)`` or
-        ``3(tau)``.
+        ``3(kinetic_energy)``.
 
         For convenience, py4vasp accepts the following aliases
 
         electronic charge density
             *charge*, *n*, *charge_density*, and *electronic_charge_density*
 
         kinetic energy density
-            *tau*, *kinetic_energy*, and *kinetic_energy_density*
+            *kinetic_energy*, *kinetic_energy*, and *kinetic_energy_density*
 
         0th component
             {component0}
@@ -367,7 +367,7 @@ def to_contour(
         Take a slice of the kinetic energy density along the first lattice vector and
         rotate it such that the normal of the plane aligns with the x axis.
 
-        >>> calc.density.to_contour("tau", a=0.3, normal="x")
+        >>> calc.density.to_contour("kinetic_energy", a=0.3, normal="x")
         """
         cut, fraction = self._get_cut(a, b, c)
         plane = slicing.plane(self._structure.lattice_vectors(), cut, normal)
@@ -427,7 +427,7 @@ def to_quiver(self, *, a=None, b=None, c=None, supercell=None, normal=None):
         first lattice vector and rotate it such that the normal of the plane aligns with
         the x axis.
 
-        >>> calc.density.to_quiver("tau", a=0.3, normal="x")
+        >>> calc.density.to_quiver("kinetic_energy", a=0.3, normal="x")
         """
         cut, fraction = self._get_cut(a, b, c)
         plane = slicing.plane(self._structure.lattice_vectors(), cut, normal)
@@ -468,9 +468,8 @@ def is_noncollinear(self):
     @property
     def _selection(self):
         selection_map = {
-            "tau": "tau",
-            "kinetic_energy": "tau",
-            "kinetic_energy_density": "tau",
+            "kinetic_energy": "kinetic_energy",
+            "kinetic_energy_density": "kinetic_energy",
         }
         return selection_map.get(super()._selection)
 

tests/calculation/test_density.py

@@ -10,7 +10,7 @@
 from py4vasp._third_party.view import Isosurface
 
 
-@pytest.fixture(params=[None, "tau"])
+@pytest.fixture(params=[None, "kinetic_energy"])
 def density_source(request):
     return request.param
 
@@ -76,7 +76,7 @@ def get_expected_dict(charge, source):
 
 def get_expected_string(selection, source):
     structure, *density = selection.split()
-    if source == "tau":
+    if source == "kinetic_energy":
         density = "Kinetic energy"
     elif not density:
         density = "Nonpolarized"
@@ -172,7 +172,7 @@ def test_collinear_plot(selection, collinear_density, Assert):
             isosurfaces=isosurfaces,
         )
         if selection in ("magnetization", "mag", "m"):
-            # magnetization not allowed for tau
+            # magnetization not allowed for kinetic_energy
             return
     check_view(collinear_density, expected, Assert, selection=selection, isolevel=0.1)
 
@@ -208,7 +208,7 @@ def test_plotting_noncollinear_density(selections, noncollinear_density, Assert)
     else:
         expected_labels = (f"{source}({selection})" for selection in selections)
         expected_density = noncollinear_density.ref.output[source][1:]
-        if "(" in selections[0]:  # magnetization not allowed for tau
+        if "(" in selections[0]:  # magnetization not allowed for kinetic_energy
             return
     isosurfaces = [
         Isosurface(isolevel=0.2, color=_config.VASP_BLUE, opacity=0.3),
@@ -296,7 +296,7 @@ def test_collinear_to_contour(selection, collinear_density, Assert):
         expected_label = f"{source}({selection})"
         expected_data = collinear_density.ref.output[source][1, :, :, 7]
         if selection in ("magnetization", "mag", "m"):
-            # magnetization not allowed for tau
+            # magnetization not allowed for kinetic_energy
             return
     expected_lattice = collinear_density.ref.structure.lattice_vectors()[:2, :2]
     graph = collinear_density.to_contour(selection, c=-0.5)
@@ -333,7 +333,7 @@ def test_noncollinear_to_contour(noncollinear_density, selections, Assert):
     else:
         expected_labels = (f"{source}({selection})" for selection in selections)
         expected_data = noncollinear_density.ref.output[source][1:, :, 5, :]
-        if "(" in selections[0]:  # magnetization not allowed for tau
+        if "(" in selections[0]:  # magnetization not allowed for kinetic_energy
             return
     graph = noncollinear_density.to_contour(" ".join(selections), b=0.4)
     expected_lattice = noncollinear_density.ref.structure.lattice_vectors()[::2, ::2]