def empty_between(cls, q0: 'Quote', q1: 'Quote') -> List['Quote']:
"""
Returns empty quotes between `q0` and `q1`.
"""
resolution = q0.resolution
if q1.resolution != q1.resolution:
raise Exception('Quote resolutions must be equal')
missing_interval = q1.start_date - q0.end_date
if missing_interval == 0:
return []
elif missing_interval < 0:
raise Exception('Quotes must be in ascending order')
ohlc = [q0.close] * 4
quotes = []
domain = Interval.intersection(
[q0.domain.get_gt(), q1.domain.get_lt()])
assert domain.is_finite
for span in resolution.iterate(domain, start_open=domain.start_open):
q = Quote(ohlc, date=span.start, volume=0.0, resolution=resolution)
quotes.append(q)
if quotes[-1].end_date > q1.start_date:
raise Exception(
f'Unregular quote distance between filled quote {quotes[-1]} and {q1}'
)
return quotes
def _update_extension_interval(self):
if not self._extension_interval_stale:
return
self._extension_interval_stale = False
if self._extension_stale:
self._update_extension_if_needed()
if self.start and self.start_valid and self.end and self.end_valid:
self.extension_interval = Interval.union([self.start_func.domain, self.end_func.domain])
elif self.start and self.start_valid:
self.extension_interval = Interval.intersection([self.start_func.domain, self.curve.domain.get_lt()])
elif self.end and self.end_valid:
self.extension_interval = Interval.intersection([self.end_func.domain, self.curve.domain.get_gt()])
else:
self.extension_interval = Interval.empty()
self.update_extension_interval()
if (self.start and not self.extension_interval.is_negative_infinite) or (self.end and not self.extension_interval.is_positive_infinite):
if self.raise_on_empty:
raise Exception('Unable to extend func')
def missing_domains(cls, quotes, domain=None):
# TODO: optimise by recursively dividing quotes
# in half and checking if the quotes are
# contiguous. Then collect domains between
# contiguous quotes.
quotes_len = len(quotes)
if quotes_len == 0:
if domain is None:
return []
else:
return [domain]
if domain is None:
domain = cls.list_domain(quotes)
else:
domain = Interval.parse(domain)
if domain.is_empty:
return []
missing_list = []
head = Interval.intersection([domain, quotes[0].domain.get_lt()])
if not head.is_empty:
missing_list.append(head)
for i in range(1, quotes_len):
q0 = quotes[i - 1]
q1 = quotes[i]
if q0.end_date != q1.start_date:
if q0.end_date > q1.start_date:
continue
missing = Interval(q0.domain.end,
q1.domain.start,
start_open=not q0.domain.end_open,
end_open=not q1.domain.start_open)
missing_list.append(missing)
tail = Interval.intersection([domain, quotes[-1].domain.get_gt()])
if not tail.is_empty:
missing_list.append(tail)
return missing_list
def sample_points(self, domain=None, min_step=MIN_STEP, step=None):
min_step = self.resolve_min_step(min_step)
if domain is None:
domain = self.domain
else:
domain = Interval.intersection([self.domain, domain])
if domain.is_empty:
return []
elif not domain.is_finite:
raise Exception(
"Cannot sample points on an infinite domain {}. Specify a finite domain."
.format(domain))
x_start, x_end = domain
x_end_bin = round(x_end / min_step) if min_step is not None else x_end
if domain.start_open:
points = []
else:
points = [(x_start, self.y(x_start))]
if step is not None:
x = x_start + step
while x <= x_end:
y = self.y(x)
points.append((x, y))
x += step
elif min_step is not None and min_step > 0:
x = self.x_next(x_start, min_step=min_step, limit=x_end)
while x is not None and x <= x_end:
y = self.y(x)
points.append((x, y))
x_bin = round(x / min_step) if min_step is not None else x
if x_bin == x_end_bin:
break
x1 = self.x_next(x, min_step=min_step, limit=x_end)
if x1 is not None:
x1_bin = round(x1 /
min_step) if min_step is not None else x1
if x1_bin <= x_bin:
raise Exception(
'Next x value {} should be greater than the previous x value {} by at least the minimum step of {}'
.format(x1, x, min_step))
x = x1
if not domain.end_open and points[-1][0] != x_end:
points.append((x_end, self.y(x_end)))
else:
raise Exception("Bad functions sample parameters.")
return points
def sample_points(self, domain=None, min_step=MIN_STEP, step=None):
min_step = self.resolve_min_step(min_step)
if domain is None:
domain = self.domain
else:
domain = Interval.intersection([self.domain, domain])
if domain.is_empty:
return []
elif domain.is_infinite:
raise Exception(
"Cannot sample points on an infinite domain. Specify a finite domain."
)
self.scan(domain.start)
self.scan(domain.end)
return super().sample_points(domain=domain,
min_step=min_step,
step=step)
def _domain_indexes(self, domain):
"""
Turn a domain into start and end indexes (inclusive and exclusive respectively).
"""
points_len = len(self._points)
if domain.is_superset_of(self.domain):
return 0, points_len
domain = Interval.intersection([domain, self.domain])
if domain.is_empty:
return 0, 0
if domain.is_negative_infinite:
start_i = 0
else:
i = max(0, int(math.floor(self.x_index(domain.start))))
while i < points_len:
x = self._points[i][0]
if x >= domain.end:
# i -= 1
break
if domain.contains(x):
break
i += 1
start_i = i
if domain.is_positive_infinite:
end_i = points_len
else:
i = min(points_len, int(math.ceil(self.x_index(domain.end))))
while i >= 0:
x = self._points[i][0]
if x <= domain.start:
# i += 1
break
if domain.contains(x):
break
i -= 1
end_i = i + 1
return start_i, end_i
def sample_points(self, domain=None, min_step=None, step=None):
domain = Interval.parse(domain, default_inf=True)
if self.domain.is_empty:
return []
if self.interval is not None and (
(min_step is not None and min_step > self.interval) or
(step is not None and step != self.interval)):
# Irregular sampling
return super().sample_points(domain=domain,
min_step=min_step,
step=step)
if domain is None or domain.is_superset_of(self.domain):
# Sample all
return list(self._points)
# Sample some
domain = Interval.intersection([self.domain, domain])
if domain.is_empty:
return []
i0, i1 = self._domain_indexes(domain)
return self._points[i0:i1]
def get_domain(self):
domains = list(map(lambda f: f.domain, self.funcs))
if self.is_union:
return Interval.union(domains)
else:
return Interval.intersection(domains)
def update_points_of_interest(self, underlying_points):
if not self.is_ready:
return False
i_end = len(underlying_points)
if i_end == 0:
return False
def process_points_on_trend(points_on_trend, insert_index):
if len(points_on_trend) == 0:
return
closest_point = None
closest_dist = 0
for p in points_on_trend:
dist = abs(self.y(p[0]) - p[1])
if closest_point is None or dist < closest_dist:
closest_dist = dist
closest_point = p
self.tangent_points.insert(insert_index, closest_point)
# find intersections, tangent points and extremas
phase = 0
phase_point = None
previous_phase = phase
intersection_found = False
intersection_insert_index = len(self.intersections)
tangent_insert_index = len(self.tangent_points)
points_on_trend = []
new_extremas = []
extrema = None
extrema_dist = 0
# search up to the last intersection or tangent point
update_interval = self.search_interval
if len(self.intersections) != 0:
update_interval = Interval.intersection(
[update_interval,
Interval.gte(self.intersections[-1][0])])
if len(self.tangent_points) != 0:
update_interval = Interval.intersection(
[update_interval,
Interval.gt(self.tangent_points[-1][0])])
for i in reversed(range(len(underlying_points))):
p = underlying_points[i]
if not update_interval.contains(p[0]):
break
if self.is_point_on_trend(p):
points_on_trend.insert(0, p)
if extrema is not None:
new_extremas.insert(0, extrema)
extrema = None
continue
elif len(points_on_trend) != 0:
process_points_on_trend(points_on_trend, tangent_insert_index)
points_on_trend = []
phase = p[1] - self.y(p[0])
at_intersection = previous_phase != 0 and phase * previous_phase < 0
if at_intersection:
# found intersection
intersection = _line_intersection(self._line, (phase_point, p))
if intersection is None or intersection[0] < self._line[0][0]:
intersection = _average_point_of_2(phase_point, p)
self.intersections.insert(intersection_insert_index,
intersection)
intersection_found = True
if extrema is not None:
new_extremas.insert(0, extrema)
extrema = None
if phase > 0:
dist = p[1]
else:
dist = -p[1]
if extrema is None or dist > extrema_dist:
extrema = p
extrema_dist = dist
previous_phase = phase
phase_point = p
if len(points_on_trend) != 0:
process_points_on_trend(points_on_trend, tangent_insert_index)
if extrema is not None:
new_extremas.insert(0, extrema)
if len(new_extremas) != 0:
# merge extremas with existing ones
if len(self.extremas) == 0:
self.extremas += new_extremas
else:
if self.extremas[-1][0] >= update_interval.start:
# old extrema may be outdated
del self.extremas[-1]
self.extremas += new_extremas
if intersection_found:
self.update_interval()
return intersection_found
def test_intersection():
# closed, closed
d1 = Interval(0, 2, start_open=False, end_open=False)
d2 = Interval(1, 3, start_open=False, end_open=False)
assert d1.contains(0)
assert d1.contains(1)
assert d1.contains(2)
d = Interval.intersection([d1, d2])
assert d.start == 1
assert d.end == 2
assert not d.start_open
assert not d.end_open
d = Interval.union([d1, d2])
assert d.start == 0
assert d.end == 3
assert not d.start_open
assert not d.end_open
# closed, open
d1 = Interval(0, 2, start_open=False, end_open=False)
d2 = Interval(1, 3, start_open=True, end_open=True)
d = Interval.intersection([d1, d2])
assert d.start == 1
assert d.end == 2
assert d.start_open
assert not d.end_open
d = Interval.union([d1, d2])
assert d.start == 0
assert d.end == 3
assert not d.start_open
assert d.end_open
# open, open
d1 = Interval(0, 2, start_open=True, end_open=True)
d2 = Interval(1, 3, start_open=True, end_open=True)
assert not d1.contains(0)
assert d1.contains(1)
assert not d1.contains(2)
d = Interval.intersection([d1, d2])
assert d.start == 1
assert d.end == 2
assert d.start_open
assert d.end_open
d = Interval.union([d1, d2])
assert d.start == 0
assert d.end == 3
assert d.start_open
assert d.end_open
d = Interval.intersection([Interval(0, 1), Interval(2, 3)])
assert d.is_empty
d = Interval.intersection([Interval(0, 1, end_open=True), Interval(1, 3, start_open=True)])
assert d.is_empty
d = Interval.intersection([Interval(0, 1), Interval.empty()])
assert d.is_empty
d = Interval.union([Interval.empty(), 1])
assert d.start == 1
assert d.end == 1
def test_intersection_inf():
assert Interval.intersection([Interval.gte(100), (98, 101)]) == (100, 101)
assert Interval.intersection([Interval.point(100), Interval.open_closed(100, 101)]) == Interval.empty()