def __cmp__(self, other):
if isinstance(other, Infinity):
d_cmp = math_tools.cmp(self.direction, other.direction)
if d_cmp != 0:
return d_cmp
else:
raise InfinityRaceError
elif is_floatable(other):
return self.direction
else:
raise NotImplementedError
def __get_node_by_monotonic_function_with_both_rounding(self, function,
value):
'''
Get a node by specifying a measure function and a desired value.
The function must be a monotonic rising function on the timeline.
The rounding option used is `binary_search.BOTH`.
Note that this function does not let you specify a tail node. Currently
we're not optimizing for the case where you have a tail node and this
function might waste resources exploring beyond it.
'''
root = self.root
cmp_root = cmp(function(root), value)
if cmp_root == 1: # function(root) > value
return (None, root)
if cmp_root == 0: # function(root) == value
return (root, root)
assert cmp_root == -1 # and function(root) < value
# Now we've established that the first node in the path has a strictly
# lower value than what we're looking for.
# A rule we will strictly obey in this function: `low` will always be a
# member whose value is lower than the desired value. (Strictly lower,
# meaning not lower-or-equal.)
low = self.root
for thing in self.iterate_blockwise():
# Rule: Every time we inspect a new node/block, `low` will be the
# node that is its immediate parent. i.e. The highest node possible
# from those that we have previously examined.
if isinstance(thing, Block):
block = thing
first = block[0]
cmp_first = cmp(function(first), value)
if cmp_first == -1: # function(first) < value
low = first
elif cmp_first == 0: # function(first) == value
return (first, first)
else: # cmp_first == 1 and function(first) > value
return (low, first)
# At this point we know that the first node in the block has a
# strictly lower value than the target value.
last = block[-1]
cmp_last = cmp(function(last), value)
if cmp_last == -1: # function(last) < value
low = last
continue
elif cmp_last == 0: # function(last) == value
return (last, last)
else: # cmp_last == 1 and function(last) > value
# The two final results are both in the block.
return binary_search.binary_search(
block, function, value, rounding=binary_search.BOTH
)
else: # thing is a Node
node = thing
cmp_node = cmp(function(node), value)
if cmp_node == -1: # function(node) < value
low = node
continue
elif cmp_node == 0: # function(node) == value
return (node, node)
else: # function(node) > value
return (low, node)
# If the flow reached here, that means that even the last node in the
# path has lower value than the value we're looking for.
return (low, None)
