WMA — Weighted Moving Average

Linearly-weighted moving average — the most recent close carries the highest weight. Single value. Draws on the price pane.

Signature

WMA(period, on=<source>)

Argument	Type	Required	Notes
period	int Param or literal	Yes	Lookback. Default 20, bounds 2–200.
on=	symbol, OHLCV field, or indicator	No	Source. Defaults to the trade symbol’s close.

Formula

$$ \text{WMA} = \frac{\sum_{i=1}^{N} i \cdot \text{close}{(i)}}{\sum{i=1}^{N} i} $$

where close₍ᵢ₎ runs oldest → newest, so the newest bar gets weight N and the oldest weight 1.

Warmup

period bars. Before the window fills, the value is the simple average of the bars observed so far.

Reading the value

wma = WMA(20, on=self.trade)

wma.value
wma > slow_sma          # comparisons read .value implicitly
wma.crossed_above(slow_sma)

Example

class WmaCross(Strategy):
    """Fast WMA crossing a slow SMA."""
    fast_period = Param(10, min=2, max=50)
    slow_period = Param(30, min=10, max=100)
    trade = Symbol()
    sizing = FixedCapital()

    def execute(self):
        fast = WMA(self.fast_period, on=self.trade)
        slow = SMA(self.slow_period, on=self.trade)
        self.stop_loss(2.0)

        if fast.crossed_above(slow) and self.trade.is_flat:
            self.buy(self.trade, reason="WMA over SMA")

        if fast.crossed_below(slow) and self.trade.is_long:
            self.sell(self.trade, self.trade.position, reason="WMA under SMA")

Notes

• Responsiveness sits between SMA (slowest) and EMA (no hard window) — WMA reacts linearly and completely forgets bars older than period.
• Same crossover mechanics as any single-value indicator — crossed_above / crossed_below work directly.