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    <p>I suggest you consider making your Point class using the <a href="http://docs.python.org/library/collections.html?highlight=namedtuple#collections.namedtuple" rel="nofollow">collections.namedtuple</a> factory function which will make it a subclass of the the built-in <code>tuple</code> class. This will save you some boiler-plate work. <code>namedtuple</code> class have attributes that can be accessed both by name, such as <code>p.x</code> and indexed, like <code>p[0]</code>. </p> <p>They are also very memory efficient like <code>tuple</code>s, which may be important if you're going to have a lot of class instances.</p> <p>You can further specialize what is returned by subclassing it, or use the <code>verbose</code> option to capture the source code and modify that as necessary.</p> <p>There's an example in the documentation linked to above showing it being used to create a 2D <code>Point</code> class, which seems like it could be very helpful in your specific use-case.</p> <p>Here's an example showing how one could define a custom 3D Point class via subclassing:</p> <pre><code>from collections import namedtuple class Point(namedtuple('Point', 'x y z')): __slots__ = () # prevent creation of instance dictionaries to save memory point_count = 0 # instance counter def __init__(self, *args): super(Point, self).__init__(*args) Point.point_count += 1 def distance(self, other): return sum((self[i]-other[i])**2 for i in xrange(len(self))) ** 0.5 def copy_point(self, distance): 'create another Point at distance from the self Point' return Point(*[dimension+distance for dimension in self]) p1 = Point(0, 0, 0) print 'p1:', p1 p2 = p1.copy_point(20) print 'p2: Point(%s)' % ', '.join(str(p2[i]) for i in xrange(len(p2))) print 'distance p1 &lt;-&gt; p2: %.3f' % p1.distance(p2) </code></pre> <p>Output:</p> <pre class="lang-none prettyprint-override"><code>p1: Point(x=1, y=2, z=3) p2: Point(21, 22, 23) distance p1 &lt;-&gt; p2: 34.641 </code></pre> <p>Note that by using <code>namedtuple</code> you don't have to implement a <code>__getitem__()</code> yourself, nor write a <code>__str__()</code> method. The only reason an <code>__init__()</code> was needed was because of the need to increment the class instance counter which was added -- something that <code>namedtuple</code>s don't have or do by default.</p>
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    1. COThank you for the interesting information
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    2. CO@AlexPi: You're welcome. FWIW, I'd also like to point out (no pun intended) that from the sample output you can see that what your `copy_point()` method does is **not** actually creating another point the specified distance away from itself. In other words `Point(21,22,23)` is not 20 units away from `Point(1,2,3)`.
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    3. COYes, I know. It was just for testing. It is not there anymore ;)
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