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Permutation python12/7/2023 However, permutation is not automatically translatable. Now len() is 2, hence the else branch of the if is taken. SOCOS can translate simple invariants automatically to Python based on built-in rules. This is trivial, since len(') is 1 then the first branch of the if condition is taken and the return value is itself (this complies with rule 2.1). Now we try to 'mental execute' it in order to shed some light for the absolute beginner. The program is a straightforward (possibly inefficient, see the remarks at the bottom of the page) implementation of the recursive algorithm. Trying to Understand the Code by 'Mental Execution' But since Pythons for loops are pretty slow, you actually get better performance for all but very tall matrices. Note that this has sub-optimal asymptotic time complexity, since the sort takes time O(n m log m) for an array of size m x n. Just like you have in the comments, when Python is doing permutations, you should, and do get 720 10 cdot 9 cdot 8. Such code is not mine, it is the original snippet the OP was asking for explanations (as a matter of fact, I am more inclined towards Lua than Python and I had to lookup the enumerate function in Python's documentation in order to fully understand the code). '''Shuffle training data''' r np.random.permutation(len(y)) return Xr, yr def initializeweights(self, m): '''Initialize weights to zeros''' self.w. This produces a random permutation of each columns indices. Im trying output all of the 3 digit permutation combinations of 0-9 and something in my code is wrong because instead of getting 1000 possible permutation combinations Im only getting 720.
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