Improved documentation for P in motifs function

Author: seanlaw

stumpy/motifs.py

@@ -205,7 +205,11 @@ def motifs(
         The time series or sequence
 
     P : numpy.ndarray
-        Matrix Profile of `T`
+        The (1-dimensional) matrix profile of `T`. In the case where the matrix
+        profile was computed with `k > 1` (i.e., top-k nearest neighbors), you
+        must summarize the top-k nearest-neighbor distances for each subsequence
+        into a single value (e.g., `np.mean`, `np.min`, etc) and that use that
+        derived value as your `P`.
 
     min_neighbors : int, default 1
         The minimum number of similar matches a subsequence needs to have in order