Sample code for the article on flattening list

Author: lpozo

python-flatten-list/README.md

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+# How to Flatten a List of Lists in Python
+
+This folder provides the code examples for the Real Python tutorial [How to Flatten a List of Lists in Python](https://realpython.com/python-flatten-list/).

python-flatten-list/flatten_comprehension.py

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+def flatten_comprehension(matrix):
+    return [item for row in matrix for item in row]

python-flatten-list/flatten_concatenation.py

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+def flatten_concatenation(matrix):
+    flat = []
+    for row in matrix:
+        flat += row
+    return flat

python-flatten-list/flatten_extend.py

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+def flatten_extend(matrix):
+    flat = []
+    for row in matrix:
+        flat.extend(row)
+    return flat

python-flatten-list/flatten_itertool_chain.py

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+from itertools import chain
+
+
+def flatten_itertools_chain(matrix):
+    return list(chain.from_iterable(matrix))

python-flatten-list/flatten_numpy_flatten.py

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+import numpy as np
+
+matrix = [list(range(100))] * 4
+arr = np.array(matrix)
+
+
+def flatten_numpy_flatten(matrix):
+    return matrix.flatten()

python-flatten-list/flatten_pandas.py

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+import pandas as pd
+
+matrix = [list(range(100))] * 4
+df = pd.DataFrame(matrix)
+
+
+def flatten_pandas(matrix):
+    return pd.DataFrame(matrix.to_numpy().flatten())

python-flatten-list/flatten_reduce_add.py

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+from functools import reduce
+from operator import add
+
+
+def flatten_reduce_add(matrix):
+    return reduce(add, matrix, [])

python-flatten-list/flatten_reduce_concat.py

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+from functools import reduce
+from operator import concat
+
+
+def flatten_reduce_concat(matrix):
+    return reduce(concat, matrix, [])

python-flatten-list/flatten_reduce_iconcat.py

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+from functools import reduce
+from operator import iconcat
+
+
+def flatten_reduce_iconcat(matrix):
+    return reduce(iconcat, matrix, [])