Method accumulator

datafusion/functions-aggregate/src/stddev.rs:118–123

(&self, acc_args: AccumulatorArgs)

    }

    fn accumulator(&self, acc_args: AccumulatorArgs) -> Result<Box<dyn Accumulator>> {
        if acc_args.is_distinct {
            return not_impl_err!("STDDEV_POP(DISTINCT) aggregations are not available");
        }
        Ok(Box::new(StddevAccumulator::try_new(StatsType::Sample)?))
    }

    fn aliases(&self) -> &[String] {
        &self.alias