Merge pull request #140 from stefmolin/rings-shape

Add Rings shape

Author: stefmolin

src/data_morph/shapes/circles.py

@@ -3,6 +3,7 @@
 from numbers import Number
 
 import matplotlib.pyplot as plt
+import numpy as np
 from matplotlib.axes import Axes
 
 from ..data.dataset import Dataset
@@ -85,37 +86,51 @@ def plot(self, ax: Axes = None) -> Axes:
         return ax
 
 
-class Bullseye(Shape):
+class Rings(Shape):
     """
-    Class representing a bullseye shape comprising two concentric circles.
+    Class representing rings comprising multiple concentric circles.
 
     .. plot::
        :scale: 75
        :caption:
             This shape is generated using the panda dataset.
 
         from data_morph.data.loader import DataLoader
-        from data_morph.shapes.circles import Bullseye
+        from data_morph.shapes.circles import Rings
 
-        _ = Bullseye(DataLoader.load_dataset('panda')).plot()
+        _ = Rings(DataLoader.load_dataset('panda')).plot()
 
     Parameters
     ----------
     dataset : Dataset
         The starting dataset to morph into other shapes.
+    num_rings : int, default 4
+        The number of rings to include. Must be greater than 1.
+
+    See Also
+    --------
+    Circle : The individual rings are represented as circles.
     """
 
-    def __init__(self, dataset: Dataset) -> None:
+    def __init__(self, dataset: Dataset, num_rings: int = 4) -> None:
+        if not isinstance(num_rings, int):
+            raise TypeError('num_rings must be an integer')
+        if num_rings <= 1:
+            raise ValueError('num_rings must be greater than 1')
+
         stdev = dataset.df.std().mean()
-        self.circles: list[Circle] = [Circle(dataset, r) for r in [stdev, stdev * 2]]
-        """list[Circle]: The inner and outer :class:`Circle` objects."""
+        self.circles: list[Circle] = [
+            Circle(dataset, r)
+            for r in np.linspace(stdev / num_rings * 2, stdev * 2, num_rings)
+        ]
+        """list[Circle]: The individual rings represented by :class:`Circle` objects."""
 
     def __repr__(self) -> str:
         return self._recursive_repr('circles')
 
     def distance(self, x: Number, y: Number) -> float:
         """
-        Calculate the minimum absolute distance between this bullseye's inner and outer
+        Calculate the minimum absolute distance between any of this shape's
         circles' edges and a point (x, y).
 
         Parameters
@@ -126,13 +141,13 @@ def distance(self, x: Number, y: Number) -> float:
         Returns
         -------
         float
-            The minimum absolute distance between this bullseye's inner and outer
+            The minimum absolute distance between any of this shape's
             circles' edges and the point (x, y).
 
         See Also
         --------
         Circle.distance :
-            A bullseye consists of two circles, so we use the minimum
+            Rings consists of multiple circles, so we use the minimum
             distance to one of the circles.
         """
         return min(circle.distance(x, y) for circle in self.circles)
@@ -155,3 +170,31 @@ def plot(self, ax: Axes = None) -> Axes:
         for circle in self.circles:
             ax = circle.plot(ax)
         return ax
+
+
+class Bullseye(Rings):
+    """
+    Class representing a bullseye shape comprising two concentric circles.
+
+    .. plot::
+       :scale: 75
+       :caption:
+            This shape is generated using the panda dataset.
+
+        from data_morph.data.loader import DataLoader
+        from data_morph.shapes.circles import Bullseye
+
+        _ = Bullseye(DataLoader.load_dataset('panda')).plot()
+
+    Parameters
+    ----------
+    dataset : Dataset
+        The starting dataset to morph into other shapes.
+
+    See Also
+    --------
+    Rings : The Bullseye is a special case where we only have 2 rings.
+    """
+
+    def __init__(self, dataset: Dataset) -> None:
+        super().__init__(dataset=dataset, num_rings=2)

src/data_morph/shapes/factory.py

@@ -51,6 +51,7 @@ class ShapeFactory:
         'up_parab': points.UpParabola,
         'diamond': polygons.Diamond,
         'rectangle': polygons.Rectangle,
+        'rings': circles.Rings,
         'star': polygons.Star,
     }
 
@@ -61,22 +62,25 @@ class ShapeFactory:
     def __init__(self, dataset: Dataset) -> None:
         self._dataset: Dataset = dataset
 
-    def generate_shape(self, shape: str) -> Shape:
+    def generate_shape(self, shape: str, **kwargs) -> Shape:
         """
         Generate the shape object based on the dataset.
 
         Parameters
         ----------
         shape : str
             The desired shape. See :attr:`.AVAILABLE_SHAPES`.
+        **kwargs
+            Additional keyword arguments to pass down when creating
+            the shape.
 
         Returns
         -------
         Shape
             An shape object of the requested type.
         """
         try:
-            return self._SHAPE_MAPPING[shape](self._dataset)
+            return self._SHAPE_MAPPING[shape](self._dataset, **kwargs)
         except KeyError as err:
             raise ValueError(f'No such shape as {shape}.') from err
 

tests/shapes/test_circles.py

@@ -71,3 +71,39 @@ def test_is_circle(self, shape):
             shape.cy + shape.r * np.sin(angles),
         ):
             assert pytest.approx(shape.distance(x, y)) == 0
+
+
+class TestRings(CirclesModuleTestBase):
+    """Test the Rings class."""
+
+    shape_name = 'rings'
+    distance_test_cases = [[(20, 50), 3.16987], [(10, 25), 9.08004]]
+    repr_regex = (
+        r'^<Rings>\n'
+        r'  circles=\n'
+        r'          <Circle cx=(\d+\.*\d*) cy=(\d+\.*\d*) r=(\d+\.*\d*)>\n'
+        r'          <Circle cx=(\d+\.*\d*) cy=(\d+\.*\d*) r=(\d+\.*\d*)>'
+    )
+
+    @pytest.mark.parametrize('num_rings', [3, 5])
+    def test_init(self, shape_factory, num_rings):
+        """Test that the Rings contains multiple concentric circles."""
+        shape = shape_factory.generate_shape(self.shape_name, num_rings=num_rings)
+
+        assert len(shape.circles) == num_rings
+        assert all(
+            getattr(circle, center_coord) == getattr(shape.circles[0], center_coord)
+            for circle in shape.circles[1:]
+            for center_coord in ['cx', 'cy']
+        )
+        assert len({circle.r for circle in shape.circles}) == num_rings
+
+    @pytest.mark.parametrize('num_rings', ['3', -5, 1, True])
+    def test_num_rings_is_valid(self, shape_factory, num_rings):
+        """Test that num_rings input validation is working."""
+        if isinstance(num_rings, int):
+            with pytest.raises(ValueError, match='num_rings must be greater than 1'):
+                _ = shape_factory.generate_shape(self.shape_name, num_rings=num_rings)
+        else:
+            with pytest.raises(TypeError, match='num_rings must be an integer'):
+                _ = shape_factory.generate_shape(self.shape_name, num_rings=num_rings)