def _calendar_span(self, date, start_open=False) -> Interval:
"""
Returns the time interval which contains the specified `date`.
"""
date = arrow.get(date)
t = self._normalized_date(date)
msec = timedelta(microseconds=1)
start = date - msec
end = date + msec
degree = self.degree
unit = self.unit
sunit = type(self).singular_unit(unit)
date_span = None
force_agr = unit == WEEKS
if force_agr:
# Special case
sunit = type(self).singular_unit(DAYS)
# Find matching unit interval (1d, 1h, etc)
for r0, r1 in arrow.Arrow.span_range(sunit, start, end):
# Normalize range end
r1 += msec
interval = Interval(r0.float_timestamp,
r1.float_timestamp,
start_open=start_open,
end_open=not start_open)
if interval.contains(t):
if degree == 1 and not force_agr:
return interval
else:
date_span = r0, r1
break
# Expand into aggregate interval
if self.unit == YEARS:
start_date, end_date = self._expand_years(date_span)
elif self.parent is not None and self.parent.unit == YEARS:
start_date, end_date = self._expand_within_year(date_span)
else:
raise Exception(f'Unable to expand unit: {self.unit}')
return Interval(self._normalized_date(start_date),
self._normalized_date(end_date),
start_open=start_open,
end_open=not start_open)
class Extremas(Scan):
# TODO: Extremas doesn't need to be a subclass of `Scan` as it only needs to find the local extrema about a point.
def __init__(self, func, ref_func, min_deviation=0, min_step=MIN_STEP):
self.ref_func = Curve.parse(ref_func)
self.min_deviation = abs(min_deviation)
self.extremas = []
self.extrema_xs = []
self.extrema_interval = Interval.empty()
self.possible_extrema = None
self.possible_extrema_phase = None
self._did_update_extremas()
super().__init__(func, self._extrema_scan, min_step=min_step)
self._ref_observer_token = self.ref_func.add_observer(
begin=self.begin_update, end=self.end_update)
def __del__(self):
self.ref_func.remove_observer(self._ref_observer_token)
def scanned_y(self, x):
if not self.extrema_interval.contains(x):
return None
if x == self.extrema_interval.start:
return self.extremas[0][1]
elif x == self.extrema_interval.end:
return self.extremas[-1][1]
i = bisect.bisect(self.extrema_xs, x)
p1 = self.extremas[i - 1]
p2 = self.extremas[i]
u = (x - p1[0]) / (p2[0] - p1[0])
return (1 - u) * p1[1] + u * p2[1]
def continue_scan(self, x):
if super().continue_scan(x):
return True
if not self.domain.contains(self.current):
return False
return not self.extrema_interval.contains(x, enforce_start=False)
def x_previous(self, x, min_step=MIN_STEP, limit=None):
min_step = self.resolve_min_step(min_step)
if self.extrema_interval.contains(x - min_step):
i = bisect.bisect_left(self.extrema_xs, x - min_step)
x1 = self.extremas[i][0]
if x1 > x - min_step:
x1 = self.extremas[i - 1][0]
return x1
return self.curve.x_previous(x, min_step=min_step, limit=limit)
def x_next(self, x, min_step=MIN_STEP, limit=None):
min_step = self.resolve_min_step(min_step)
if self.extrema_interval.contains(x + min_step):
i = bisect.bisect_left(self.extrema_xs, x + min_step)
x1 = self.extremas[i][0]
if x1 < x + min_step:
x1 = self.extremas[i + 1][0]
return x1
return self.curve.x_next(x, min_step=min_step, limit=limit)
def begin_update(self, domain):
super().begin_update(domain)
# remove stale points
for i in reversed(range(len(self.extremas))):
x = self.extrema_xs[i]
if domain.contains(x):
self._remove_extrema_index(i)
elif domain.start > x:
break
# scan from last extrema
extrema_count = len(self.extremas)
if extrema_count == 0:
self.current = None
else:
last_extrema = self.extremas[-1]
x = last_extrema[0]
self.current = x
self.possible_extrema = last_extrema
self.possible_extrema_phase = last_extrema[1] - self.ref_func(x)
def sample_points(self, domain=None, min_step=MIN_STEP, step=None):
points = super().sample_points(domain=domain,
min_step=min_step,
step=step)
return list(filter(lambda p: p[1] is not None, points))
def _extrema_scan(self, x, y):
if y is None:
return
y0 = self.ref_func(x)
if y0 is None:
return
div = y / y0 - 1
if abs(div) <= self.min_deviation:
# function is too close to reference function
return
phase = y - y0
if self.possible_extrema is None:
self.possible_extrema = (x, y)
self.possible_extrema_phase = phase
return
is_possible_extrema = False
if self.possible_extrema_phase * phase < 0:
# phase inflection
self._confirm_extrema()
is_possible_extrema = True
elif (phase > 0 and y > self.possible_extrema[1]) or (
phase < 0 and y < self.possible_extrema[1]):
is_possible_extrema = True
if is_possible_extrema:
self.possible_extrema = (x, y)
self.possible_extrema_phase = phase
def _remove_extrema_index(self, i):
del self.extremas[i]
del self.extrema_xs[i]
self._did_update_extremas()
def _confirm_extrema(self):
extrema = self.possible_extrema
self.extremas.append(extrema)
self.extrema_xs.append(extrema[0])
self._did_update_extremas()
def _did_update_extremas(self):
self.possible_extrema = None
self.possible_extrema_phase = None
if len(self.extremas) == 0:
self.extrema_interval = Interval.empty()
else:
self.extrema_interval = Interval(self.extrema_xs[0],
self.extrema_xs[-1],
start_open=False,
end_open=False)
def _i(self, x):
if not self.extrema_interval.contains(x):
return None
if x == self.extrema_interval.start:
return 0
elif x == self.extrema_interval.end:
return len(self.extremas) - 1
i = bisect.bisect(self.extrema_xs, x)
p1 = self.extremas[i - 1]
p2 = self.extremas[i]
u = (x - p1[0]) / (p2[0] - p1[0])
return i + u
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
