def build(self, name: Optional[str] = None): return WindowellExpression( partition_by=self.partition_by, order_by=self.order_by, frame=self.frame, name=name ) 3.1 Window Composition class WindowComposer: """Compose multiple window expressions""" @staticmethod def chain(window1: WindowellExpression, window2: WindowellExpression): """Chain windows: apply window2 on window1's result""" return WindowellExpression( partition_by=window1.partition_by + window2.partition_by, order_by=window1.order_by + window2.order_by, frame=window2.frame or window1.frame )
def __init__(self): self.window_registry: dict[str, WindowellExpression] = {} windowell expressions
def range_between(self, start: int, end: int): self.frame = WindowFrame( start=(start, FrameBound.PRECEDING), end=(end, FrameBound.FOLLOWING), frame_type="range" ) return self order_by=window1.order_by + window2.order_by
def setUp(self): self.engine = WindowellEngine() self.df = pd.DataFrame( 'product': ['A', 'A', 'A', 'B', 'B'], 'date': pd.date_range('2024-01-01', periods=5), 'sales': [100, 150, 200, 50, 75] ) WindowellExpression] = {} def range_between(self
@dataclass class WindowellExpression: partition_by: List[str] order_by: List[str] frame: Optional[WindowFrame] = None name: Optional[str] = None
def evaluate(self, df: pd.DataFrame) -> int: return self.expression(df) dynamic_window = WindowellBuilder() .partition("category") .order("timestamp") .rows_between( DynamicBoundary(lambda df: df['lag'].max()), "preceding", 0, "current_row" ).build() 4. Testing Suite import unittest class TestWindowellExpressions(unittest.TestCase):