Abaco — Math Engine for Rust

Italian/Spanish: abacus

Abaco is a Rust math engine providing expression evaluation and unit conversion. Shared library crate for the AGNOS ecosystem.

Pure Rust, zero unsafe — minimal dependencies, 99%+ test coverage.

Features

Module	Description
`core`	Value types (Integer, Float, Fraction, Complex, Text), Unit, UnitCategory (14 categories), Currency
`eval`	Tokenizer, recursive descent parser, 28+ math functions, variables, scientific notation, percentage shorthand
`units`	Unit registry with 100+ built-in units, HashMap-indexed O(1) lookups, SI + IEC data sizes
`dsp`	Audio DSP math primitives — dB conversion, MIDI↔frequency, envelope time constants, PolyBLEP, panning, crossfade
`ai`	Natural language math parsing, calculation history (feature-gated)

Quick Start

[dependencies]
abaco = "0.22"

# With natural language parsing:
# abaco = { version = "0.22", features = ["ai"] }

use abaco::{Evaluator, UnitRegistry};

// Evaluate expressions
let eval = Evaluator::new();
let result = eval.eval("2 + 3 * 4").unwrap();
assert_eq!(result.to_string(), "14");

let result = eval.eval("sqrt(144) + sin(pi / 2)").unwrap();
assert_eq!(result.to_string(), "13");

// Percentage shorthand
let result = eval.eval("200 * 15%").unwrap();
assert_eq!(result.to_string(), "30");

// Variables
let mut eval = Evaluator::new();
eval.set_variable("x", 5.0);
let result = eval.eval("x ^ 2 + 1").unwrap();
assert_eq!(result.to_string(), "26");

// Unit conversion
let registry = UnitRegistry::new();
let r = registry.convert(100.0, "celsius", "fahrenheit").unwrap();
assert!((r.to_value - 212.0).abs() < 0.1);

// SI and IEC data sizes
let r = registry.convert(1.0, "GB", "GiB").unwrap();
assert!((r.to_value - 0.931).abs() < 0.001);

Feature Flags

Feature	Default	Description	Extra deps
`ai`	no	Natural language math parsing, calculation history	reqwest, tokio
`full`	—	All optional features	(same as ai)

Consumers

Project	Uses
Abacus	Desktop calculator GUI, CLI, REPL, MCP tools
Impetus	Unit conversions, expression evaluation for physics simulation

Supported Functions (28+)

Trig: sin, cos, tan, asin, acos, atan, atan2 Hyperbolic: sinh, cosh, tanh, asinh, acosh, atanh Logarithmic: log (log10), ln, log2 Rounding: ceil, floor, round, trunc, fract Other: sqrt, abs, exp, sign/sgn, deg, rad, min, max, pow

Unit Categories (14)

Length, Mass, Temperature, Time, DataSize (SI + IEC), Speed, Area, Volume, Energy, Pressure, Angle, Frequency, Force, Power

100+ units with case-insensitive lookup, plural forms, and case-sensitive symbol distinction (mW vs MW).

License

AGPL-3.0-only

abaco 1.1.0