Merge pull request #53 from chris-greening/add-cycloid-cusp-routine

Add cusp routine factory method

.pylintrc

@@ -198,7 +198,8 @@ good-names=i,
            d,
            ax,
            R,
-           r
+           r,
+           n
 
 # Good variable names regexes, separated by a comma. If names match any regex,
 # they will always be accepted

setup.py

@@ -7,7 +7,7 @@
 
 setuptools.setup(
     name="spyrograph",
-    version="0.13.0",
+    version="0.14.0",
     author="Chris Greening",
     author_email="chris@christophergreening.com",
     description="Library for drawing spirographs in Python",

spyrograph/_cycloid.py

@@ -0,0 +1,25 @@
+"""Abstract base class for generalizing the hypocycloid and epicycloid
+shape's methods i.e. tracing, calculating, etc.
+"""
+
+from abc import ABC
+from numbers import Number
+from typing import List
+
+class _Cycloid(ABC):
+    # pylint: disable=too-few-public-methods
+    @classmethod
+    def n_cusps(
+            cls, R: Number, n: int, thetas: List[Number] = None,
+            theta_start: Number = None, theta_stop: Number = None,
+            theta_step: Number = None
+        ) -> "Cycloid":
+        """Return a cycloid with n number of cusps"""
+        return cls(
+            R=R,
+            r=R/n,
+            thetas=thetas,
+            theta_start=theta_start,
+            theta_stop=theta_stop,
+            theta_step=theta_step
+        )

spyrograph/_roulette.py → spyrograph/_trochoid.py

@@ -22,7 +22,7 @@
 except ImportError:
     pd = None
 
-class _Roulette(ABC):
+class _Trochoid(ABC):
     def __init__(
             self, R: Number, r: Number, d: Number, thetas: List[Number] = None,
             theta_start: Number = None, theta_stop: Number = None,

spyrograph/epitrochoid/__init__.py

@@ -2,6 +2,6 @@
 
 from spyrograph.epitrochoid.epitrochoid import Epitrochoid
 from spyrograph.epitrochoid.epicycloid import Epicycloid
-from spyrograph.epitrochoid.cardioid import Cardioid
-from spyrograph.epitrochoid.nephroid import Nephroid
-from spyrograph.epitrochoid.ranuncloid import Ranuncloid
+from spyrograph.epitrochoid.special.cardioid import Cardioid
+from spyrograph.epitrochoid.special.nephroid import Nephroid
+from spyrograph.epitrochoid.special.ranuncloid import Ranuncloid

spyrograph/epitrochoid/epicycloid.py

@@ -6,8 +6,9 @@
 from numbers import Number
 
 from spyrograph.epitrochoid.epitrochoid import Epitrochoid
+from spyrograph._cycloid import _Cycloid
 
-class Epicycloid(Epitrochoid):
+class Epicycloid(_Cycloid, Epitrochoid):
     """Model of a epicycloid which is a special case of a epitrochoid where the
     circle is rolling around the outside of the fixed circle and has 1/3 the
     radius of the fixed circle

spyrograph/epitrochoid/epitrochoid.py

@@ -5,9 +5,9 @@
 import math
 from numbers import Number
 
-from spyrograph._roulette import _Roulette
+from spyrograph._trochoid import _Trochoid
 
-class Epitrochoid(_Roulette):
+class Epitrochoid(_Trochoid):
     """Model of a epitrochoid"""
     def _circle_offset(self) -> Number:
         """Return rolling circle offset from fixed circle"""

spyrograph/hypotrochoid/__init__.py

@@ -2,7 +2,7 @@
 
 from spyrograph.hypotrochoid.hypotrochoid import Hypotrochoid
 from spyrograph.hypotrochoid.hypocycloid import Hypocycloid
-from spyrograph.hypotrochoid.deltoid import Deltoid
-from spyrograph.hypotrochoid.astroid import Astroid
-from spyrograph.hypotrochoid.ellipse import Ellipse
-from spyrograph.hypotrochoid.tusi_couple import TusiCouple
+from spyrograph.hypotrochoid.special.deltoid import Deltoid
+from spyrograph.hypotrochoid.special.astroid import Astroid
+from spyrograph.hypotrochoid.special.ellipse import Ellipse
+from spyrograph.hypotrochoid.special.tusi_couple import TusiCouple

spyrograph/hypotrochoid/hypocycloid.py

@@ -6,8 +6,9 @@
 from numbers import Number
 
 from spyrograph.hypotrochoid.hypotrochoid import Hypotrochoid
+from spyrograph._cycloid import _Cycloid
 
-class Hypocycloid(Hypotrochoid):
+class Hypocycloid(_Cycloid, Hypotrochoid):
     """Model of a hypocycloid which is a special case of a hypotrochoid where
     the circle is rolling around the inside of the fixed circle and has 1/3
     the radius of the fixed circle

spyrograph/hypotrochoid/hypotrochoid.py

@@ -5,9 +5,9 @@
 import math
 from numbers import Number
 
-from spyrograph._roulette import _Roulette
+from spyrograph._trochoid import _Trochoid
 
-class Hypotrochoid(_Roulette):
+class Hypotrochoid(_Trochoid):
     """Model of a hypotrochoid"""
     def _circle_offset(self) -> Number:
         """Return rolling circle offset from fixed circle"""

tests/_roulette.py

@@ -121,3 +121,13 @@ def test_multiple_thetas_exception(self, thetas: "np.array") -> None:
     def test_rolling_radius_equals_distance(self, instance):
         """Test radius of rolling circle is equal to distance"""
         assert instance.r == instance.d
+
+    def test_n_cusps(self, thetas):
+        """Test the n cusps factory method"""
+        for n in range(2, 5):
+            obj = self.class_name.n_cusps(
+                R = 300,
+                n = n,
+                thetas = thetas
+            )
+            assert obj.r == obj.R/n