Most pythonic way of rotating a circular list to a canonical point

Lukas Barth mail at tinloaf.de
Sun Aug 2 00:51:53 CEST 2015


On Saturday, August 1, 2015 at 11:37:48 PM UTC+2, Emile van Sebille wrote:
> Well, it looks to me that I don't know what a 'canonical rotation' is -- 

That's because it is not defined. ;)

I need a way to rotate one of these lists in a way so that it will produce the same output every time, regardless of what the input rotation was.

Example:

[0,1,2,3,4] => [0,1,2,3,4]
[2,3,4,0,1] => [0,1,2,3,4]
[3,4,0,1,2] => [0,1,2,3,4]
...

It doesn't have to be "[0,1,2,3,4]", it can just as well be [2,3,4,1,0], as long as it's always the same.

Did that make it clearer?

Thanks a lot,

Lukas


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