constants library

Physical, astronomical, and engineering constants for the quantify package.

This library provides type-safe access to fundamental constants with appropriate units from physics, astronomy, and engineering. By importing this single file, you gain access to all three constant categories.

Usage

import 'package:quantify/quantify.dart';
import 'package:quantify/constants.dart';

void main() {
  // Physical constants are now type-safe Quantities where possible
  final lightSpeed = PhysicalConstants.speedOfLight; // Returns a Speed object
  final electronEnergy = PhysicalConstants.electronRestEnergy; // Returns an Energy object

  // Astronomical constants
  final earthGravity = AstronomicalConstants.standardGravity; // Returns an Acceleration object
  final sunPower = AstronomicalConstants.solarLuminosity; // Returns a Power object

  // Engineering constants
  final steelStiffness = EngineeringConstants.steelYoungsModulus; // Returns a Pressure object

  // Use in convenience methods for powerful, type-safe calculations
  final photonEnergy = PhysicalConstants.photonEnergy(500.0.nm);
  final escapeVelocity = AstronomicalConstants.escapeVelocity(
    AstronomicalConstants.earthMass,
    AstronomicalConstants.earthRadius,
  );

  print('Speed of light: ${lightSpeed.asKilometersPerHour}');
  print('Earth standard gravity: ${earthGravity.asMetersPerSecondSquared}');
  print('Energy of a 500nm photon: ${photonEnergy.inElectronvolts.toStringAsFixed(2)} eV');
}

Constant Categories

PhysicalConstants

Fundamental constants from physics including the speed of light, Planck constant, elementary charge, particle masses, quantum and electromagnetic constants, and convenience methods for common physics calculations.

AstronomicalConstants

Constants from astronomy and astrophysics including solar system body properties (masses, radii, distances), galactic and cosmological scales, stellar physics constants, and convenience methods for orbital mechanics.

EngineeringConstants

Practical constants for engineering including standard conditions (STP, NTP), material properties (density, strength), mechanical properties (Young's modulus), and convenience methods for common engineering calculations.