Python Sort list of lists numerically

Question

I have a list of x,y coordinates and I want to sort them based on the x coordinate, then y coordinate when x is the same and eliminate duplicates of the same coordinates. For example, if the list is:

[[450.0, 486.6], [500.0, 400.0], [450.0, 313.3], [350.0, 313.3], [300.0, 400.0],
 [349.9, 486.6], [450.0, 313.3]]
 

I want to rearrange it to:

[[300.0, 400.0], [349.9, 486.6], [350.0, 313.3], [450.0, 313.3], [450.0, 486.6],
 [500.0, 400.0]]

Can anyone tell me the solution?

Answer 1

You can try and De-dupe it with a dict.

>>> L = [[450.0, 486.6], [500.0, 400.0], [450.0, 313.3], [350.0, 313.3], [300.0, 400.0], [349.9, 486.6], [450.0, 313.3]]
>>> sorted({tuple(x): x for x in L}.values())
[[300.0, 400.0],
 [349.9, 486.6],
 [350.0, 313.3],
 [450.0, 313.3],
 [450.0, 486.6],
 [500.0, 400.0]]