# The MIT License (MIT) # Copyright (c) 2014-2017 University of Bristol
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
# DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
# OR OTHER DEALINGS IN THE SOFTWARE.
from ..stream import StreamInstance
[docs]def count(data):
cnt = 0
for _ in data:
cnt += 1
return cnt
[docs]def any_set(data):
for dt, val in data:
if val:
return True
return False
[docs]def online_sum(data, total=0.0):
for x in data:
total += x.value if isinstance(x, StreamInstance) else x
return total
[docs]def online_product(data, total=1.0):
for x in data:
total *= x.value if isinstance(x, StreamInstance) else x
return total
[docs]def online_average(data, n=0, mean=0.0):
for x in data:
n += 1
delta = (x.value if isinstance(x, StreamInstance) else x) - mean
mean += delta / n
# TODO from niall: Possibly unnecessary bug: np.mean([1]) = 1. Suggest (n < 1)
if n < 1:
return float('nan')
else:
return mean
[docs]def online_variance(data, n=0, mean=0.0, m2=0.0):
for x in data:
n += 1
x = x.value if isinstance(x, StreamInstance) else x
delta = x - mean
mean += delta / n
m2 += delta * (x - mean)
if n < 2:
return float('nan')
else:
return m2 / (n - 1)