jakevdp/scipy — comment on commit 0ae5661ce613cae15a46787774473231b6cda8b1
File: scipy/spatial/distance.py line 1761
By WarrenWeckesser:

You can drop the transpose (^T) here--no point in taking the transpose of a scalar.

To be consistent with its use in other formulas, you should keep the "underscore 2" that indicates a 2-norm.