def __init__(self, *args, **kwargs):
"""Create a Vega Grouped Bar Chart"""
if 'grouped' not in kwargs:
kwargs['grouped'] = True
super(GroupedBar, self).__init__(*args, **kwargs)
del self.data['stats']
del self.scales['y'].type
self.scales['y'].domain.field = 'data.val'
self.scales['y'].domain.data = 'table'
self.scales['x'].padding = 0.2
del self.marks[0].from_.transform[1]
self.marks[0].from_.transform[0].keys[0] = 'data.idx'
enter_props = PropertySet(x=ValueRef(scale='x', field="key"),
width=ValueRef(scale='x', band=True))
self.marks[0].properties = MarkProperties(enter=enter_props)
self.marks[0].scales = KeyedList()
self.marks[0].scales['pos'] = Scale(name='pos', type='ordinal',
range='width',
domain=DataRef(field='data.group'))
self.marks[0].marks[0].properties.enter.width.scale = 'pos'
self.marks[0].marks[0].properties.enter.y.field = 'data.val'
self.marks[0].marks[0].properties.enter.x.field = 'data.group'
self.marks[0].marks[0].properties.enter.x.scale = 'pos'
del self.marks[0].marks[0].properties.enter.y2.field
self.marks[0].marks[0].properties.enter.y2.value = 0
def __init__(self, *args, **kwargs):
"""Initialize a Visualization
In addition to setting any attributes, this sets the data, marks,
scales, and axes properties to empty KeyedLists if they aren't
defined by the arguments.
"""
super(Visualization, self).__init__(*args, **kwargs)
for attrib in ('data', 'scales'):
if not getattr(self, attrib):
setattr(self, attrib, KeyedList(attr_name='name'))
# The axes get keyed by "type" instead of name.
if not self.axes:
self.axes = KeyedList(attr_name='type')
# Marks and Legends don't get keyed.
if not self.marks:
self.marks = []
if not self.legends:
self.legends = []
