52 lines
1.3 KiB
GDScript3
52 lines
1.3 KiB
GDScript3
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class AverageValue:
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var sum : float
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var count : int
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func _init(sum_, count_):
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self.sum = sum_
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self.count = count_
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static func average_(
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key_mapper = null
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) -> Callable:
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var average = func(source : Observable) -> Observable:
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# """Partially applied average operator.
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#
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# Computes the average of an observable sequence of values that
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# are in the sequence or obtained by invoking a transform
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# function on each element of the input sequence if present.
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#
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# Examples:
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# >>> var res = average.call(source)
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#
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# Args:
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# source: Source observable to average.
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#
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# Returns:
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# An observable sequence containing a single element with the
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# average of the sequence of values.
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# """
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@warning_ignore("incompatible_ternary")
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var key_mapper_ : Callable = key_mapper if key_mapper != null else func(x): return float(x)
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var accumulator = func(prev : AverageValue, curr : float) -> AverageValue:
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return AverageValue.new(prev.sum + curr, prev.count + 1)
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var mapper = func(s : AverageValue) -> float:
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if s.count == 0:
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BadMappingError.new("Input Sequence was empty!").throw()
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return NAN
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return s.sum / float(s.count)
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var seed_ = AverageValue.new(0, 0)
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var ret = source.pipe4(
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GDRx.op.map(key_mapper_),
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GDRx.op.scan(accumulator, seed_),
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GDRx.op.last(),
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GDRx.op.map(mapper)
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)
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return ret
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return average
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