Files
Aura/crates/aura-std/src/abs.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

80 lines
2.3 KiB
Rust

//! `Abs` — one-input f64 absolute value. Turns a signed delta (e.g. the
//! negative-side split of a price change) into a positive magnitude, e.g.
//! RSI-class signals' `loss = Abs(Min(delta, 0))`. Emits `None` until its
//! input has a value.
use aura_core::{Cell, Ctx, FieldSpec, Firing, Node, NodeSchema, PortSpec, PrimitiveBuilder, ScalarKind};
/// One-input f64 absolute value, `value.abs()`. Emits `None` until its input
/// has a value (warm-up filter, C8).
pub struct Abs {
out: [Cell; 1],
}
impl Abs {
pub fn new() -> Self {
Self { out: [Cell::from_f64(0.0)] }
}
pub fn builder() -> PrimitiveBuilder {
PrimitiveBuilder::new(
"Abs",
NodeSchema {
inputs: vec![PortSpec { kind: ScalarKind::F64, firing: Firing::Any, name: "value".into() }],
output: vec![FieldSpec { name: "value".into(), kind: ScalarKind::F64 }],
params: vec![],
doc: "absolute value of the input series",
},
|_| Box::new(Abs::new()),
)
}
}
impl Default for Abs {
fn default() -> Self {
Self::new()
}
}
impl Node for Abs {
fn lookbacks(&self) -> Vec<usize> {
vec![1]
}
fn eval(&mut self, ctx: Ctx<'_>) -> Option<&[Cell]> {
let w = ctx.f64_in(0);
if w.is_empty() {
return None;
}
self.out[0] = Cell::from_f64(w[0].abs());
Some(&self.out)
}
fn label(&self) -> String {
"Abs".to_string()
}
}
#[cfg(test)]
mod tests {
use super::*;
use aura_core::{AnyColumn, Scalar, Timestamp};
#[test]
fn abs_of_negative_and_positive_is_the_magnitude() {
let mut a = Abs::new();
let mut inputs = vec![AnyColumn::with_capacity(ScalarKind::F64, 1)];
inputs[0].push(Scalar::f64(-3.0)).unwrap();
assert_eq!(a.eval(Ctx::new(&inputs, Timestamp(0))), Some([Cell::from_f64(3.0)].as_slice()));
inputs[0].push(Scalar::f64(3.0)).unwrap();
assert_eq!(a.eval(Ctx::new(&inputs, Timestamp(0))), Some([Cell::from_f64(3.0)].as_slice()));
}
#[test]
fn abs_is_none_until_input_present() {
let mut a = Abs::new();
let inputs = vec![AnyColumn::with_capacity(ScalarKind::F64, 1)];
assert_eq!(a.eval(Ctx::new(&inputs, Timestamp(0))), None);
}
}