[FEATURE] Add wrappers for more sklearn datasets

prototorch/datasets/__init__.py

@@ -1,8 +1,6 @@
 """ProtoTorch datasets."""
 
 from .abstract import NumpyDataset
-from .iris import Iris
+from .sklearn import Blobs, Circles, Iris, Moons, Random
 from .spiral import Spiral
 from .tecator import Tecator
-
-__all__ = ['Iris', 'Spiral', 'Tecator']

prototorch/datasets/iris.py

@@ -1,40 +0,0 @@
-"""Thin wrapper for the Iris classification dataset from sklearn.
-
-URL:
-    https://scikit-learn.org/stable/modules/generated/sklearn.datasets.load_iris.html
-
-"""
-
-from typing import Sequence
-
-from prototorch.datasets.abstract import NumpyDataset
-from sklearn.datasets import load_iris
-
-
-class Iris(NumpyDataset):
-    """
-    Iris Dataset by Ronald Fisher introduced in 1936.
-
-    The dataset contains four measurements from flowers of three species of iris.
-
-    .. list-table:: Iris
-        :header-rows: 1
-
-        * - dimensions
-          - classes
-          - training size
-          - validation size
-          - test size
-        * - 4
-          - 3
-          - 150
-          - 0
-          - 0
-
-    :param dims: select a subset of dimensions
-    """
-    def __init__(self, dims: Sequence[int] = None):
-        x, y = load_iris(return_X_y=True)
-        if dims:
-            x = x[:, dims]
-        super().__init__(x, y)

prototorch/datasets/sklearn.py

@@ -0,0 +1,137 @@
+"""Thin wrappers for a few scikit-learn datasets.
+
+URL:
+    https://scikit-learn.org/stable/modules/classes.html#module-sklearn.datasets
+
+"""
+
+import warnings
+from typing import Sequence, Union
+
+from prototorch.datasets.abstract import NumpyDataset
+
+from sklearn.datasets import (load_iris, make_blobs, make_circles,
+                              make_classification, make_moons)
+
+
+class Iris(NumpyDataset):
+    """Iris Dataset by Ronald Fisher introduced in 1936.
+
+    The dataset contains four measurements from flowers of three species of iris.
+
+    .. list-table:: Iris
+        :header-rows: 1
+
+        * - dimensions
+          - classes
+          - training size
+          - validation size
+          - test size
+        * - 4
+          - 3
+          - 150
+          - 0
+          - 0
+
+    :param dims: select a subset of dimensions
+    """
+    def __init__(self, dims: Sequence[int] = None):
+        x, y = load_iris(return_X_y=True)
+        if dims:
+            x = x[:, dims]
+        super().__init__(x, y)
+
+
+class Blobs(NumpyDataset):
+    """Generate isotropic Gaussian blobs for clustering.
+
+    Read more at
+    https://scikit-learn.org/stable/datasets/sample_generators.html#sample-generators.
+
+    """
+    def __init__(self,
+                 num_samples: int = 300,
+                 num_features: int = 2,
+                 seed: Union[None, int] = 0):
+        x, y = make_blobs(num_samples,
+                          num_features,
+                          centers=None,
+                          random_state=seed,
+                          shuffle=False)
+        super().__init__(x, y)
+
+
+class Random(NumpyDataset):
+    """Generate a random n-class classification problem.
+
+    Read more at
+    https://scikit-learn.org/stable/modules/generated/sklearn.datasets.make_classification.html.
+
+    Note: n_classes * n_clusters_per_class <= 2**n_informative must satisfy.
+    """
+    def __init__(self,
+                 num_samples: int = 300,
+                 num_features: int = 2,
+                 num_classes: int = 2,
+                 num_clusters: int = 2,
+                 num_informative: Union[None, int] = None,
+                 separation: float = 1.0,
+                 seed: Union[None, int] = 0):
+        if not num_informative:
+            import math
+            num_informative = math.ceil(math.log2(num_classes * num_clusters))
+            if num_features < num_informative:
+                warnings.warn("Generating more features than requested.")
+                num_features = num_informative
+        x, y = make_classification(num_samples,
+                                   num_features,
+                                   n_informative=num_informative,
+                                   n_redundant=0,
+                                   n_classes=num_classes,
+                                   n_clusters_per_class=num_clusters,
+                                   class_sep=separation,
+                                   random_state=seed,
+                                   shuffle=False)
+        super().__init__(x, y)
+
+
+class Circles(NumpyDataset):
+    """Make a large circle containing a smaller circle in 2D.
+
+    A simple toy dataset to visualize clustering and classification algorithms.
+
+    Read more at
+    https://scikit-learn.org/stable/modules/generated/sklearn.datasets.make_circles.html
+
+    """
+    def __init__(self,
+                 num_samples: int = 300,
+                 noise: float = 0.3,
+                 factor: float = 0.8,
+                 seed: Union[None, int] = 0):
+        x, y = make_circles(num_samples,
+                            noise=noise,
+                            factor=factor,
+                            random_state=seed,
+                            shuffle=False)
+        super().__init__(x, y)
+
+
+class Moons(NumpyDataset):
+    """Make two interleaving half circles.
+
+    A simple toy dataset to visualize clustering and classification algorithms.
+
+    Read more at
+    https://scikit-learn.org/stable/modules/generated/sklearn.datasets.make_moons.html
+
+    """
+    def __init__(self,
+                 num_samples: int = 300,
+                 noise: float = 0.3,
+                 seed: Union[None, int] = 0):
+        x, y = make_moons(num_samples,
+                          noise=noise,
+                          random_state=seed,
+                          shuffle=False)
+        super().__init__(x, y)