def cloud_for_model(self, model, steps=4, distribution=LOGARITHMIC,
filters=None, min_count=None):
"""
Obtain a list of tags associated with instances of the given
Model, giving each tag a ``count`` attribute indicating how
many times it has been used and a ``font_size`` attribute for
use in displaying a tag cloud.
``steps`` defines the range of font sizes - ``font_size`` will
be an integer between 1 and ``steps`` (inclusive).
``distribution`` defines the type of font size distribution
algorithm which will be used - logarithmic or linear. It must
be either ``tagging.utils.LOGARITHMIC`` or
``tagging.utils.LINEAR``.
To limit the tags displayed in the cloud to those associated
with a subset of the Model's instances, pass a dictionary of
field lookups to be applied to the given Model as the
``filters`` argument.
To limit the tags displayed in the cloud to those with a
``count`` greater than or equal to ``min_count``, pass a value
for the ``min_count`` argument.
"""
tags = list(self.usage_for_model(model, counts=True, filters=filters,
min_count=min_count))
return calculate_cloud(tags, steps, distribution)
def test_linear_distribution(self):
sizes = {}
for tag in calculate_cloud(self.tags, steps=5, distribution=LINEAR):
sizes[tag.font_size] = sizes.get(tag.font_size, 0) + 1
# This isn't a pre-calculated test, just making sure it's consistent
self.assertEquals(sizes[1], 97)
self.assertEquals(sizes[2], 12)
self.assertEquals(sizes[3], 7)
self.assertEquals(sizes[4], 2)
self.assertEquals(sizes[5], 4)
def test_default_distribution(self):
sizes = {}
for tag in calculate_cloud(self.tags, steps=5):
sizes[tag.font_size] = sizes.get(tag.font_size, 0) + 1
# This isn't a pre-calculated test, just making sure it's consistent
self.assertEquals(sizes[1], 48)
self.assertEquals(sizes[2], 30)
self.assertEquals(sizes[3], 19)
self.assertEquals(sizes[4], 15)
self.assertEquals(sizes[5], 10)
def test_invalid_distribution(self):
try:
calculate_cloud(self.tags, steps=5, distribution="cheese")
except ValueError, ve:
self.assertEquals(str(ve), "Invalid distribution algorithm specified: cheese.")
