Files
Aura/crates/aura-std/src/mul.rs
T
claude a32dc38d18 feat(std): meaning lines for all 27 shipped node schemas
C29 compile/unit seam, task 3 of the self-description plan: every
aura-std NodeSchema literal threads its one-line doc. Four texts were
corrected against the actual eval/finalize semantics rather than taken
from the plan table verbatim: Delay is a lag-N register (not one-step),
GatedRecorder flushes an ungated final row at finalize, Latch is a
level-sensitive set/reset register (captures no input), SeriesReducer
emits its single summary row at finalize (not per cycle).

Gate: cargo build -p aura-std --lib clean; full std test run follows at
the all-crates gate once strategy/backtest/engine thread their sites
(the earlier per-crate test gate was unsatisfiable in isolation --
std's dev-deps pull crates whose sites belong to later tasks).

refs #316
2026-07-23 15:25:16 +02:00

75 lines
2.4 KiB
Rust

//! `Mul` — two-input f64 product (input 0 times input 1). The fundamental
//! multiplication primitive (e.g. squaring a return for a variance estimate:
//! `Mul(delta, delta)`). Emits `None` until both inputs have a value.
use aura_core::{Cell, Ctx, FieldSpec, Firing, Node, NodeSchema, PortSpec, PrimitiveBuilder, ScalarKind};
/// Two-input f64 product: input 0 times input 1. Emits `None` until both inputs
/// have a value.
pub struct Mul {
out: [Cell; 1],
}
impl Mul {
pub fn new() -> Self {
Self { out: [Cell::from_f64(0.0)] }
}
pub fn builder() -> PrimitiveBuilder {
PrimitiveBuilder::new(
"Mul",
NodeSchema {
inputs: vec![
PortSpec { kind: ScalarKind::F64, firing: Firing::Any, name: "lhs".into() },
PortSpec { kind: ScalarKind::F64, firing: Firing::Any, name: "rhs".into() },
],
output: vec![FieldSpec { name: "value".into(), kind: ScalarKind::F64 }],
params: vec![],
doc: "elementwise product of two input series",
},
|_| Box::new(Mul::new()),
)
}
}
impl Default for Mul {
fn default() -> Self { Self::new() }
}
impl Node for Mul {
fn lookbacks(&self) -> Vec<usize> { vec![1, 1] }
fn eval(&mut self, ctx: Ctx<'_>) -> Option<&[Cell]> {
let a = ctx.f64_in(0);
let b = ctx.f64_in(1);
if a.is_empty() || b.is_empty() {
return None;
}
self.out[0] = Cell::from_f64(a[0] * b[0]);
Some(&self.out)
}
fn label(&self) -> String { "Mul".to_string() }
}
#[cfg(test)]
mod tests {
use super::*;
use aura_core::{AnyColumn, Scalar, Timestamp};
#[test]
fn mul_is_product_once_both_inputs_present() {
let mut m = Mul::new();
let mut inputs = vec![
AnyColumn::with_capacity(ScalarKind::F64, 1),
AnyColumn::with_capacity(ScalarKind::F64, 1),
];
inputs[0].push(Scalar::f64(3.0)).unwrap();
assert_eq!(m.eval(Ctx::new(&inputs, Timestamp(0))), None); // only one leg
inputs[1].push(Scalar::f64(4.0)).unwrap();
assert_eq!(m.eval(Ctx::new(&inputs, Timestamp(0))), Some([Cell::from_f64(12.0)].as_slice()));
}
#[test]
fn input_slots_are_named_lhs_rhs() {
let names: Vec<String> = Mul::builder().schema().inputs.iter().map(|p| p.name.clone()).collect();
assert_eq!(names, ["lhs", "rhs"]);
}
}