class OWItemsets(widget.OWWidget):
name = 'Frequent Itemsets'
description = 'Explore sets of items that frequently appear together.'
icon = 'icons/FrequentItemsets.svg'
priority = 10
class Inputs:
data = Input("Data", Table)
class Outputs:
matching_data = Output("Matching Data", Table)
class Error(widget.OWWidget.Error):
need_discrete_data = widget.Msg(
"Need some discrete data to work with.")
no_disc_features = widget.Msg(
"Discrete features required but data has none.")
class Warning(widget.OWWidget.Warning):
cont_attrs = widget.Msg(
"Data has continuous attributes which will be skipped.")
err_reg_expression = widget.Msg("Error in regular expression: {}")
minSupport = settings.Setting(30)
maxItemsets = settings.Setting(10000)
filterSearch = settings.Setting(True)
autoFind = settings.Setting(False)
autoSend = settings.Setting(True)
filterKeywords = settings.Setting('')
filterMinItems = settings.Setting(1)
filterMaxItems = settings.Setting(10000)
UserAdviceMessages = [
widget.Message(
'Itemset are listed in item-sorted order, i.e. '
'an itemset containing A and B is only listed once, as '
'A > B (and not also B > A).', 'itemsets-order',
widget.Message.Warning),
widget.Message(
'To select all the itemsets that are descendants of '
'(include) some item X (i.e. the whole subtree), you '
'can fold the subtree at that item and then select it.',
'itemsets-order', widget.Message.Information)
]
def __init__(self):
self.data = None
self.output = None
self._is_running = False
self.isRegexMatch = lambda x: True
self.tree = QTreeWidget(self.mainArea,
columnCount=2,
allColumnsShowFocus=True,
alternatingRowColors=True,
selectionMode=QTreeWidget.ExtendedSelection,
uniformRowHeights=True)
self.tree.setHeaderLabels(["Itemsets", "Support", "%"])
self.tree.header().setStretchLastSection(True)
self.tree.itemSelectionChanged.connect(self.selectionChanged)
self.mainArea.layout().addWidget(self.tree)
box = gui.widgetBox(self.controlArea, "Info")
self.nItemsets = self.nSelectedExamples = self.nSelectedItemsets = ''
gui.label(box, self, "Number of itemsets: %(nItemsets)s")
gui.label(box, self, "Selected itemsets: %(nSelectedItemsets)s")
gui.label(box, self, "Selected examples: %(nSelectedExamples)s")
hbox = gui.widgetBox(box, orientation='horizontal')
gui.button(hbox, self, "Expand all", callback=self.tree.expandAll)
gui.button(hbox, self, "Collapse all", callback=self.tree.collapseAll)
box = gui.widgetBox(self.controlArea, 'Find itemsets')
gui.valueSlider(box,
self,
'minSupport',
values=[.0001, .0005, .001, .005, .01, .05, .1, .5] +
list(range(1, 101)),
label='Minimal support:',
labelFormat="%g%%",
callback=lambda: self.find_itemsets())
gui.hSlider(box,
self,
'maxItemsets',
minValue=10000,
maxValue=100000,
step=10000,
label='Max. number of itemsets:',
labelFormat="%d",
callback=lambda: self.find_itemsets())
self.button = gui.auto_commit(
box,
self,
'autoFind',
'Find Itemsets',
commit=self.find_itemsets,
callback=lambda: self.autoFind and self.find_itemsets())
box = gui.widgetBox(self.controlArea, 'Filter itemsets')
gui.lineEdit(box,
self,
'filterKeywords',
'Contains:',
callback=self.filter_change,
orientation='horizontal',
tooltip='A comma or space-separated list of regular '
'expressions.')
hbox = gui.widgetBox(box, orientation='horizontal')
gui.spin(hbox,
self,
'filterMinItems',
1,
998,
label='Min. items:',
callback=self.filter_change)
gui.spin(hbox,
self,
'filterMaxItems',
2,
999,
label='Max. items:',
callback=self.filter_change)
gui.checkBox(box,
self,
'filterSearch',
label='Apply these filters in search',
tooltip='If checked, the itemsets are filtered according '
'to these filter conditions already in the search '
'phase. \nIf unchecked, the only filters applied '
'during search are the ones above, '
'and the itemsets are \nfiltered afterwards only for '
'display, i.e. only the matching itemsets are shown.')
gui.rubber(hbox)
gui.rubber(self.controlArea)
gui.auto_commit(self.controlArea, self, 'autoSend', 'Send selection')
self.filter_change()
ITEM_DATA_ROLE = Qt.UserRole + 1
def selectionChanged(self):
X = self.X
mapping = self.onehot_mapping
instances = set()
where = np.where
def whole_subtree(node):
yield node
for i in range(node.childCount()):
yield from whole_subtree(node.child(i))
def itemset(node):
while node:
yield node.data(0, self.ITEM_DATA_ROLE)
node = node.parent()
def selection_ranges(node):
n_children = node.childCount()
if n_children:
yield (self.tree.indexFromItem(node.child(0)),
self.tree.indexFromItem(node.child(n_children - 1)))
for i in range(n_children):
yield from selection_ranges(node.child(i))
nSelectedItemsets = 0
item_selection = QItemSelection()
for node in self.tree.selectedItems():
nodes = (node, ) if node.isExpanded() else whole_subtree(node)
if not node.isExpanded():
for srange in selection_ranges(node):
item_selection.select(*srange)
for node in nodes:
nSelectedItemsets += 1
cols, vals = zip(*(mapping[i] for i in itemset(node)))
if issparse(X):
rows = (len(cols) == np.bincount(
(X[:, cols] != 0).indices,
minlength=X.shape[0])).nonzero()[0]
else:
rows = where((X[:, cols] == vals).all(axis=1))[0]
instances.update(rows)
self.tree.itemSelectionChanged.disconnect(self.selectionChanged)
self.tree.selectionModel().select(
item_selection,
QItemSelectionModel.Select | QItemSelectionModel.Rows)
self.tree.itemSelectionChanged.connect(self.selectionChanged)
self.nSelectedExamples = len(instances)
self.nSelectedItemsets = nSelectedItemsets
self.output = self.data[sorted(instances)] or None
self.commit()
def commit(self):
self.Outputs.matching_data.send(self.output)
def filter_change(self):
self.Warning.err_reg_expression.clear()
try:
isRegexMatch = self.isRegexMatch = re.compile(
'|'.join(
i.strip()
for i in re.split('(,|\s)+', self.filterKeywords.strip())
if i.strip()), re.IGNORECASE).search
except Exception as e:
self.Warning.err_reg_expression(e.args[0])
isRegexMatch = self.isRegexMatch = lambda x: True
def hide(node, depth, has_kw):
if not has_kw:
has_kw = isRegexMatch(node.text(0))
hidden = (
sum(
hide(node.child(i), depth + 1, has_kw)
for i in range(node.childCount())) == node.childCount()
if node.childCount() else
(not has_kw
or not self.filterMinItems <= depth <= self.filterMaxItems))
node.setHidden(hidden)
return hidden
hide(self.tree.invisibleRootItem(), 0, False)
class TreeWidgetItem(QTreeWidgetItem):
def data(self, column, role):
"""Construct lazy tooltips"""
if role != Qt.ToolTipRole:
return super().data(column, role)
tooltip = []
while self:
tooltip.append(self.text(0))
self = self.parent()
return '\n'.join(reversed(tooltip))
def find_itemsets(self):
if self.data is None or not len(self.data):
return
if self._is_running:
self._is_running = False
return
self._is_running = True
self.button.button.setText('Cancel')
data = self.data
self.tree.clear()
self.tree.setUpdatesEnabled(False)
self.tree.blockSignals(True)
class ItemDict(dict):
def __init__(self, item):
self.item = item
top = ItemDict(self.tree.invisibleRootItem())
X, mapping = OneHot.encode(data)
self.Error.need_discrete_data.clear()
if X is None:
self.Error.need_discrete_data()
self.onehot_mapping = mapping
ITEM_FMT = '{}' if issparse(data.X) else '{}={}'
names = {
item: ITEM_FMT.format(var.name, val)
for item, var, val in OneHot.decode(mapping.keys(), data, mapping)
}
nItemsets = 0
filterSearch = self.filterSearch
filterMinItems, filterMaxItems = self.filterMinItems, self.filterMaxItems
isRegexMatch = self.isRegexMatch
# Find itemsets and populate the TreeView
with self.progressBar(self.maxItemsets + 1) as progress:
for itemset, support in frequent_itemsets(X,
self.minSupport / 100):
if filterSearch and not filterMinItems <= len(
itemset) <= filterMaxItems:
continue
parent = top
first_new_item = None
itemset_matches_filter = False
for item in sorted(itemset):
name = names[item]
if filterSearch and not itemset_matches_filter:
itemset_matches_filter = isRegexMatch(name)
child = parent.get(name)
if child is None:
try:
wi = self.TreeWidgetItem(parent.item, [
name,
str(support), '{:.4g}'.format(
100 * support / len(data))
])
except RuntimeError:
# FIXME: When autoFind was in effect and the support
# slider was moved, this line excepted with:
# RuntimeError: wrapped C/C++ object of type
# TreeWidgetItem has been deleted
return
wi.setData(0, self.ITEM_DATA_ROLE, item)
child = parent[name] = ItemDict(wi)
if first_new_item is None:
first_new_item = (parent, name)
parent = child
if filterSearch and not itemset_matches_filter:
parent, name = first_new_item
parent.item.removeChild(parent[name].item)
del parent[name].item
del parent[name]
else:
nItemsets += 1
progress.advance()
if not self._is_running or nItemsets >= self.maxItemsets:
break
qApp.processEvents()
if not filterSearch:
self.filter_change()
self.nItemsets = nItemsets
self.nSelectedItemsets = 0
self.nSelectedExamples = 0
self.tree.expandAll()
for i in range(self.tree.columnCount()):
self.tree.resizeColumnToContents(i)
self.tree.setUpdatesEnabled(True)
self.tree.blockSignals(False)
self._is_running = False
self.button.button.setText('Find Itemsets')
@Inputs.data
def set_data(self, data):
self.data = data
is_error = False
if data is not None:
self.Warning.cont_attrs.clear()
self.Error.no_disc_features.clear()
self.button.setDisabled(False)
self.X = data.X
if issparse(data.X):
self.X = data.X.tocsc()
else:
if not data.domain.has_discrete_attributes():
self.Error.no_disc_features()
is_error = True
self.button.setDisabled(True)
elif data.domain.has_continuous_attributes():
self.Warning.cont_attrs()
else:
self.output = None
self.commit()
if self.autoFind and not is_error:
self.find_itemsets()
