Permute list in place

src/delphi/train/permute.py

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+# Number number generation utils without using any library
+
+
+class Permutation:
+    """
+    Permutation class
+    Atributes:
+    - state: int, seed for the random number generator
+
+    """
+
+    def __init__(self, seed):
+        self.state = seed
+
+    def set_seed(self, seed):
+        """
+        Set the seed
+        """
+        self.state = seed
+
+    def permute(self, list):
+        """
+        Permute a list in place using Fisher-Yates shuffle
+        """
+        for i in range(len(list)):
+            j = int(self.random_number_generator() * (i + 1))
+            # self.state = self.state + 1
+            list[i], list[j] = list[j], list[i]
+        return list
+
+    def random_number_generator(self):
+        """
+        Generate a random number between 0 and 1 using minstd_rand from C++11
+        """
+        self.state = (self.state * 48271) % 4294967296
+        return self.state / 4294967296

tests/test_permutations.py

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+from delphi.train.permute import Permutation
+
+
+def test_permute():
+
+    perm = Permutation(1)
+
+    # Test the random number generator
+    for i in range(100000):
+        assert perm.random_number_generator() >= 0
+        assert perm.random_number_generator() <= 1
+    state = perm.state
+    assert state == 822144001
+    # Test the permutation
+    test_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+    length = len(test_list)
+    for i in range(100000):
+        perm.permute(test_list)
+        assert len(test_list) == length
+    assert test_list == [5, 6, 4, 10, 7, 2, 1, 3, 8, 9]