matplotlib legend location numbers

Question

I am beginning to use Python for my scientific computing, and I am really liking it a lot, however I am confused by a feature of the matplotlib.pylab.legend function. In particular, the location feature allows one to specifiy the location of their legend using numbers, following this scheme:

• best -- 0
• upper right -- 1
• upper left -- 2
• lower left -- 3
• lower right -- 4
• right -- 5
• center left -- 6
• center right -- 7
• lower center -- 8
• upper center -- 9
• center -- 10

Does anyone know why you wouldn't use the ordering on the numpad? I.e. center -- 5, upper right -- 9, etc.

I am just curious if anyone knows.

Answer 1

The docs show this example:

legend( ('label1', 'label2', 'label3'), loc='upper left')

Presumably, you could write loc=2, but why would you? It's much more readable to use the English word.

As to why they didn't enumerate the values to align with the numeric keypad, I presume they weren't thinking about the numeric keypad at the time.

Edit: It's worth including here the full text of Joe Kington's comment:

Actually, they were deliberately mimicking matlab's behavior at the time. See the "obsolete location values" section in the documentation for MATLAB's legend: mathworks.com/help/techdoc/ref/legend.html