This is a short interlude.
The NumPy Ravel function returns the flattened form of the array. Why ravel?
The word ravel is both a synonym and antonym of unravel. Ravel in real-life is illustrated nicely by this drawing:
How did it get into NumPy? Interestingly the function ravel (with same meaning) was already present in APL/360 in 1968.
Which reminds me that the old (2001) Numerical Python user manual1 includes the line:
The languages which were used to guide the development of NumPy include the infamous APL family of languages, ...
David Ascher, Paul F. Dubois, Konrad Hinsen, Jim Hugunin, Travis Oliphant et al, September 7, 2001, Lawrence Livermore National Laboratory, Livermore, CA 94566, UCRL-MA-128569 ↩