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POeliminating redundant tuples
 

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    <p>If I have a list of tuples, where each tuple represents variables, <code>a</code>, <code>b</code> and <code>c</code>, how can I eliminate redundant tuples?</p> <p>Redundant tuples are those where <code>a</code> and <code>b</code> are simply interchanged, but <code>c</code> is the same. So for this example:</p> <pre><code>tups = [(30, 40, 50), (40, 30, 50), (20, 48, 52), (48, 20, 52)] </code></pre> <p>my final list should only contain only half of the entries. One possible output:</p> <pre><code>tups = [(30, 40, 50), (20, 48, 52)] </code></pre> <p>another</p> <pre><code>tups = [(40, 30, 50), (20, 48, 52)] </code></pre> <p>etc.</p> <p>Is there an easy Pythonic way to do this? </p> <p>I tried using sets, but <code>(30, 40, 50)</code> is different from <code>(40, 30, 50)</code>, but to me these are redundant and I'd just like to keep one of them (doesn't matter which, but if I could pick I'd prefer the low to high value order). If there was a way to sort the first 2 elements of the tuples, then using the set would work.</p> <p>I am sure I could hack together a working solution (perhaps converting tuples to lists as intermediate step), but I just wanted to see if there's an easy and obvious way to do this that I'm not familiar with.</p> <p>PS: This question partially motivated by <a href="http://projecteuler.net/problem=39" rel="nofollow">PE #39</a>. But even aside from this PE problem, I am now just curious how this could be done easily (or if).</p> <p><strong>Edit</strong>:</p> <p>Just to provide a bit of context for those not familiar with PE #39 - <code>a</code>, <code>b</code>, and <code>c</code> represent sides of a right triangle, so I'm checking if <code>a**2 + b**2 == c**2</code>, clearly the order of <code>a</code> and <code>b</code> don't matter.</p>
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    1. COActually, `set((30, 40, 50)) == set((40, 30, 50))`.
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    2. CO@Lenna: But, `set([(30, 40, 50), (40, 30, 50)]) != set([(30, 40, 50)])`.
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    3. CO@JoelCornett: I was referring to the OP's statement, "I tried using sets, but `(30, 40, 50)` is different from `(40, 30, 50)`"
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