@Flavin, excellent. It has been noted here before that numpy is such a large and complex library that it may fail to load properly.

@iacoposk8 This would be a good use of pdb, since you could look at what you are appending each cycle in the loop. Or, just print out something in each loop such as part.shape. I wonder if this isn't just a display issue (things getting overwritten or omitted?)... have you actually checked the type/sizes of the elements in x?

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