def join_subsequences_by_sign_of_elements(sequence):
'''Join subsequences in `sequence` by sign of elements.
::
>>> sequence = [[1, 2], [3, 4], [-5, -6, -7], [-8, -9, -10], [11, 12]]
>>> sequencetools.join_subsequences_by_sign_of_elements(sequence)
[[1, 2, 3, 4], [-5, -6, -7, -8, -9, -10], [11, 12]]
::
>>> sequence = [[1, 2], [], [], [3, 4, 5], [6, 7]]
>>> sequencetools.join_subsequences_by_sign_of_elements(sequence)
[[1, 2], [], [3, 4, 5, 6, 7]]
Returns new list.
'''
if not isinstance(sequence, list):
raise TypeError
if not all(isinstance(x, list) for x in sequence):
raise TypeError
if any(mathtools.get_shared_numeric_sign(x) is None for x in sequence):
raise ValueError
result = []
for sublist in sequence:
try:
previous_sublist = result[-1]
if mathtools.get_shared_numeric_sign(previous_sublist) == \
mathtools.get_shared_numeric_sign(sublist):
previous_sublist.extend(sublist)
else:
result.append(sublist[:])
except IndexError:
result.append(sublist[:])
return result
def lengths_to_joined_positive_counts(sequence):
'''Return a list of positive counts grouped into sublists.
::
>>> import lidercfeny
::
>>> sequence = [1, -1, -2, 1, -2, -1, -2, 2, 1, -3, -1, 2, -2, -1, -1]
>>> lidercfeny.etc.transforms.lengths_to_joined_positive_counts(sequence)
[[1], [5], [11, 12, 13], [18, 19]]
'''
result = baca.tools.map_elements_to_numbered_sublists(sequence)
result = sequencetools.join_subsequences_by_sign_of_elements(result)
result = [x for x in result if mathtools.get_shared_numeric_sign(x) == 1]
return result
def test_mathtools_get_shared_numeric_sign_01():
assert mathtools.get_shared_numeric_sign([1, 2, 3]) == 1
assert mathtools.get_shared_numeric_sign([-1, -2, -3]) == -1
assert mathtools.get_shared_numeric_sign([]) == 0
assert mathtools.get_shared_numeric_sign([1, 2, -3]) is None
def join_subsequences_by_sign_of_elements(sequence):
'''Joins subsequences in `sequence` by sign of elements.
.. container:: example
**Example 1.** Joins lists by sign of elements:
::
>>> sequence = [[1, 2], [3, 4], [-5, -6, -7], [-8, -9, -10], [11, 12]]
>>> sequencetools.join_subsequences_by_sign_of_elements(sequence)
[[1, 2, 3, 4], [-5, -6, -7, -8, -9, -10], [11, 12]]
.. container:: example
**Example 2.** Works with empty lists:
::
>>> sequence = [[1, 2], [], [], [3, 4, 5], [6, 7]]
>>> sequencetools.join_subsequences_by_sign_of_elements(sequence)
[[1, 2], [], [3, 4, 5, 6, 7]]
.. container:: example
**Example 3.** Joins tuples by sign of elements:
::
>>> sequence = [(1, 2), (), (), (3, 4, 5), (6, 7)]
>>> sequencetools.join_subsequences_by_sign_of_elements(sequence)
[(1, 2), (), (3, 4, 5, 6, 7)]
Returns new list.
'''
if not isinstance(sequence, collections.Sequence):
message = 'must be sequence: {!r}.'
message = message.format(sequence)
raise Exception(message)
if not all(isinstance(x, collections.Sequence) for x in sequence):
message = 'must contain only sequences: {!r}.'
message = message.format(sequence)
raise Exception(message)
if any(mathtools.get_shared_numeric_sign(x) is None for x in sequence):
raise ValueError
sequence_type = type(sequence)
result = []
for subsequence in sequence:
try:
previous_subsequence = result[-1]
previous_subsequence_type = type(previous_subsequence)
previous_sublist = list(previous_subsequence)
if mathtools.get_shared_numeric_sign(previous_subsequence) == \
mathtools.get_shared_numeric_sign(subsequence):
previous_sublist.extend(subsequence)
previous_subsequence = previous_subsequence_type(
previous_sublist)
result[-1] = previous_subsequence
else:
result.append(subsequence[:])
except IndexError:
result.append(subsequence[:])
result = sequence_type(result)
return result
