Question

I’m trying to write out the coordinates of a 3d object, but I’m not sure how to list it.

so far I have:

class threed:
    def __init__(self,length,width,height):
        self.h =height
        self.l = length
        self.w = width
        self.f=0
        self.lwh = (length,width,height)

for i in range(1,3):
      for j in range(1,3):
           for k in range(1,3):
                coordinates=threed(i,j,k)

The problem is my function rewrites the variable coordinates each time so that I can’t ever access coordinate (1,1,1) for example.

Note the above is for a 2x2x2 object.

How do I write it efficiently so that I can reference any coordinate as I need?

Answer 1

You can do:

[threed(*x) for x in itertools.product(range(1, 3), range(1,3), range(1,3))]

to have each object. You may also use 3 for loops as well:

[threed(x, y, z) for x in range(1, 3) for y in range(1,3) for z in range(1,3)]

---

Adding the __repr__ method to your class, you can see more easily the result.

def __repr__(self):
    return 'threed' + repr(self.lwh)

So the output of the first code will be:

[threed(1, 1, 1), threed(1, 1, 2), threed(1, 2, 1), threed(1, 2, 2), 
 threed(2, 1, 1), threed(2, 1, 2), threed(2, 2, 1), threed(2, 2, 2)]

---

To allow threed objects to be compared, you can add a __eq__ method:

def __eq__(self, other):
    return self.lwh == other.lwh