Off course, you are right. I'll quickly fix this bug! Thanks for reporting. 2012/12/18 Patrice Munger <patricemunger@gmail.com>:

Comparing the code in regionprops.py with the reference http://www.cs.qub.ac.uk/~d.crookes/webpubs/papers/perimeter.doc, should line 450 be (1 + sqrt(2) )/ 2: (13, 23) rather than 1 + sqrt(2) / 2: (13, 23) ?

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