def running_sum(start=None):
"""Running sum co-routine.
With no arguments, ``running_sum`` consumes values and returns the
running sum of arguments sent to it:
>>> rsum = running_sum()
>>> rsum.send(1)
1
>>> [rsum.send(n) for n in (2, 3, 4)]
[3, 6, 10]
If optional argument ``start`` is given and is not None, it is used as
the initial value for the running sum:
>>> rsum = running_sum(9)
>>> [rsum.send(n) for n in (1, 2, 3)]
[10, 12, 15]
"""
if start is None:
partials = []
else:
partials = [start]
x = (yield None)
while True:
add_partial(partials, x)
x = (yield _builtin_sum(partials))
def count(iterable=None):
if isinstance(iterable, (Expr, core.FExpr)):
return Expr(OpCodes.COUNT, (iterable, ))
elif iterable is None:
return Expr(OpCodes.COUNT0, ())
else:
return _builtin_sum((x is not None) for x in iterable)
def count(iterable=None):
if isinstance(iterable, Expr):
return Expr(OpCodes.COUNT, iterable)
elif iterable is None:
return Expr(OpCodes.COUNT0)
else:
return _builtin_sum((x is not None) for x in iterable)
def sum(iterable, start=0):
if isinstance(iterable, (Expr, core.FExpr)):
return Expr(OpCodes.SUM, (iterable, ))
else:
return _builtin_sum(iterable, start)
def sum(iterable, start=0):
if isinstance(iterable, Expr):
return Expr(OpCodes.SUM, iterable)
else:
return _builtin_sum(iterable, start)