Merge pull request #23 from pjotrp/master

Removing pylmm out of the GN2 tree

1 files changed, 96 insertions, 0 deletions

diff --git a/wqflask/utility/chunks.py b/wqflask/utility/chunks.py
new file mode 100644
index 00000000..9565fb96
--- /dev/null
+++ b/wqflask/utility/chunks.py
@@ -0,0 +1,96 @@
+from __future__ import absolute_import, print_function, division
+
+import math
+import time
+
+
+def divide_into_chunks(the_list, number_chunks):
+    """Divides a list into approximately number_chunks smaller lists
+    
+    >>> divide_into_chunks([1, 2, 7, 3, 22, 8, 5, 22, 333], 3)
+    [[1, 2, 7], [3, 22, 8], [5, 22, 333]]
+    >>> divide_into_chunks([1, 2, 7, 3, 22, 8, 5, 22, 333], 4)                                                                                                                                                     
+    [[1, 2, 7], [3, 22, 8], [5, 22, 333]]
+    >>> divide_into_chunks([1, 2, 7, 3, 22, 8, 5, 22, 333], 5)                                                                                                                                                     
+    [[1, 2], [7, 3], [22, 8], [5, 22], [333]]
+    >>>
+    
+    """
+    length = len(the_list)
+
+    if length == 0:
+        return [[]]
+    
+    if length <= number_chunks:
+        number_chunks = length
+
+    chunksize = int(math.ceil(length / number_chunks))
+
+    chunks = []
+    for counter in range(0, length, chunksize):
+        chunks.append(the_list[counter:counter+chunksize])
+
+    return chunks
+
+def _confirm_chunk(original, result):
+    all_chunked = []
+    for chunk in result:
+        all_chunked.extend(chunk)
+    print("length of all chunked:", len(all_chunked))
+    assert original == all_chunked, "You didn't chunk right"
+
+
+def _chunk_test(divide_func):
+    import random
+    random.seed(7)
+
+    number_exact = 0
+    total_amount_off = 0
+
+    for test in range(1, 1001):
+        print("\n\ntest:", test)
+        number_chunks = random.randint(1, 20)
+        number_elements = random.randint(0, 100)
+        the_list = list(range(1, number_elements))
+        result = divide_func(the_list, number_chunks)
+
+        print("Dividing list of length {} into approximately {} chunks - got {} chunks".format(
+            len(the_list), number_chunks, len(result)))
+        print("result:", result)
+
+        _confirm_chunk(the_list, result)
+
+        amount_off = abs(number_chunks - len(result))
+        if amount_off == 0:
+            number_exact += 1
+        else:
+            total_amount_off += amount_off
+
+
+        print("\n{} exact out of {}    [Total amount off: {}]".format(number_exact,
+                                                                      test,
+                                                                      total_amount_off))
+    assert number_exact == 558
+    assert total_amount_off == 1580
+    return number_exact, total_amount_off
+
+
+def _main():
+    info = dict()
+    #funcs = (("sam", sam_divide_into_chunks), ("zach", zach_divide_into_chunks))
+    funcs = (("only one", divide_into_chunks),)
+    for name, func in funcs:
+        start = time.time()
+        number_exact, total_amount_off = _chunk_test(func)
+        took = time.time() - start
+        info[name] = dict(number_exact=number_exact,
+                          total_amount_off=total_amount_off,
+                          took=took)
+
+    print("info is:", info)
+
+if __name__ == '__main__':
+    _main()
+    print("\nConfirming doctests...")
+    import doctest
+    doctest.testmod()