def fpgrowth(fptree, min_support=2, pruning=False):
'''Finds frequent item sets of items appearing in a list of transactions
based on FP-Growth by Han et al.
:param fptree: The input of the algorithm. Must come from
`get_fptree`.
:param min_support: The minimal support of a set.
:param pruning: Perform a pruning operation. Default to False.
:rtype: A set containing the frequent item sets and their support.
'''
fis = set()
report = {}
_fpgrowth(fptree, fis, report, min_support, pruning)
return report
def fpgrowth(fptree, min_support=2, pruning=False):
'''Finds frequent item sets of items appearing in a list of transactions
based on FP-Growth by Han et al.
:param fptree: The input of the algorithm. Must come from
`get_fptree`.
:param min_support: The minimal support of a set.
:param pruning: Perform a pruning operation. Default to False.
:rtype: A set containing the frequent item sets and their support.
'''
fis = set()
report = {}
_fpgrowth(fptree, fis, report, min_support, pruning)
return report
def test_fpgrowth(should_print=False, ts=None, support=2, pruning=False):
if ts is None:
ts = get_default_transactions()
fptree = get_fptree(ts, lambda e: e, support)
fis = set()
report = {}
n = _fpgrowth(fptree, fis, report, support, pruning)
if should_print:
print(n)
print(report)
return (n, report)
def test_fpgrowth(should_print=False, ts=None, support=2, pruning=False):
if ts is None:
ts = get_default_transactions()
fptree = get_fptree(ts, lambda e: e, support)
fis = set()
report = {}
n = _fpgrowth(fptree, fis, report, support, pruning)
if should_print:
print(n)
print(report)
return (n, report)
def _fpgrowth(fptree, fis, report, min_support=2, pruning=True):
(_, heads) = fptree
n = 0
for (head_node, head_support) in heads.values():
if head_support < min_support:
continue
fis.add(head_node.key)
#print('Report {0} with support {1}'.format(fis, head_support))
report[frozenset(fis)] = head_support
new_heads = _init_heads(heads)
_create_cond_tree(head_node, new_heads, pruning)
if pruning:
_prune_cond_tree(new_heads, min_support)
n = n + 1 + _fpgrowth((None, new_heads), fis, report, min_support,
pruning)
fis.remove(head_node.key)
return n
def _fpgrowth(fptree, fis, report, min_support=2, pruning=True):
(_, heads) = fptree
n = 0
for (head_node, head_support) in heads.values():
if head_support < min_support:
continue
fis.add(head_node.key)
#print('Report {0} with support {1}'.format(fis, head_support))
report[frozenset(fis)] = head_support
new_heads = _init_heads(heads)
_create_cond_tree(head_node, new_heads, pruning)
if pruning:
_prune_cond_tree(new_heads, min_support)
n = n + 1 + _fpgrowth(
(None, new_heads), fis, report, min_support, pruning)
fis.remove(head_node.key)
return n
