chore: import upstream snapshot with attribution

2026-07-13 13:30:25 +08:00
commit f19b2512d7
562 changed files with 38082 additions and 0 deletions
@@ -0,0 +1,28 @@
+import numpy as np
+
+
+class Kernel(object):
+    """
+    Base class for kernel function
+    """
+
+    def _pairwise(self, x, y):
+        """
+        all pairs of x and y
+
+        Parameters
+        ----------
+        x : (sample_size, n_features)
+            input
+        y : (sample_size, n_features)
+            another input
+
+        Returns
+        -------
+        output : tuple
+            two array with shape (sample_size, sample_size, n_features)
+        """
+        return (
+            np.tile(x, (len(y), 1, 1)).transpose(1, 0, 2),
+            np.tile(y, (len(x), 1, 1))
+        )