json-to-equation, a light weight library leveraging big.js to perform precise arithmetic operations using json notation.

Features

• JSON-Based Expressions: Perform arithmetic operations using JSON notation for easy and readable mathematical expressions.
• Expressions are tree strcutured, can be nested to any levels.
• Support for Common Operators: Includes support for addition, subtraction, multiplication, division, and exponentiation.
• Provides accurate values for important mathematical constants.
• Big Number Precision: Utilizes big.js for high-precision arithmetic calculations.

Installation

npm install json-to-equation --save

Usage

Importing the Library

import { Constants, evaluate } from 'json-to-equation';

Basic Expressions

console.log(evaluate({
  $add: [15,5]
})); // Output: 15

console.log(evaluate({
    $add: [100, {
        $mul: [
            {
                $add: [1, 2]
            }, // Result : 3 
            {
                $exp : [10, 2]
            } // Result : 100 
        ] // Result : 400 
    }]
})) // Output: 400

Complex Expressions

Express complex equations in JSON notation.

Newtons law of universal gravitation can be expressed as:

import { Constants, evaluate } from 'json-to-equation';

const m1 = 10; 
const m2 = 20;
const r = 12

console.log(evaluate({
    $mul : [
        Constants.Physics.G, // Universal Gravitational Constant
        {
            $div : [
                {
                    $mul : [m1, m2]
                },
                 {
                    $mul : [r, r]
                },
            ]
        }
    ]
})) 

Expression Formats

• Expressions should be provided as objects with a single key representing the operator, and an array of operands which can be numbers or nested expressions.
• The operhands array can contain only two values, which can be either a value or another nested expression, so that it can always be respresented as an expression tree.

Valid Expressions

// 1 + 2 
const  addingTwoNumbers = evaluate({
    $add : [1,2] // Result =  3 
})

// 1 + ( 2 + 3 )
const  addingThreeNumbers = evaluate({
    $add : [1, {
        $add : [2,3] // Result = 5
    }] // Result = 6
})

// 10 * 6
const multiplicationExample= evaluate({
    $mul : [10, 6] // Result = 60
})

// 2 * 10^2
const multiplicationAndExponent= evaluate({
    $mul : [2, {
        $exp : [10,2]
    }]
})

Invalid Expressions

// The Wrong Way  
const  addingThreeNumbers = evaluate({
    $add : [1,2,3] // Error : Operhands array can have only two values
})

// The Correct Way
const  addingThreeNumbers = evaluate({
    $add : [1, {
        $add : [2,3]
    }] // Result = 6 , Note: Operhands array right now have two values 
})

Supported Operators

• $add: Adds two numbers or expressions.
• $sub: Subtracts the second number or expression from the first.
• $mul: Multiplies two numbers or expressions.
• $div: Divides the first number or expression by the second.
• $exp: Raises the first number or expression to the power of the second

Constants

Accessing Constants

import { Constants } from 'json-to-equation';

console.log(Constants.Physics.C); // Output: Speed of light - 299792458
console.log(Constants.Math.PI);   // Output: Pi - 3.141592653589793
console.log(Constants.Math.PI);   // Output: Faraday constant - 96485.33212

Physics

| Symbol | Definition | Accessor | |--------------|-----------------------------------------------|---------------------------| | C | Speed of light in vacuum (m/s) | Constants.Physics.C | | G | Newton's Universal Gravitation Constant (m³ kg⁻¹ s⁻²) | Constants.Physics.G | | h | Planck's constant (J s) | Constants.Physics.h | | e | Elementary charge (C) | Constants.Physics.e | | ε0 | Vacuum permittivity (F/m) | Constants.Physics.epsilon_0 | | α | Fine-structure constant (dimensionless) | Constants.Physics.alpha |

Maths

| Symbol | Definition | Accessor | |-------------|-----------------------------------|---------------------------| | π | Pi | Constants.Math.PI | | e | Euler's number | Constants.Math.e | | φ | Golden ratio | Constants.Math.phi | | √2 | Square root of 2 | Constants.Math.sqrt2 | | п | Natural logarithm of 2 | Constants.Math.ln2 | | н10 | Natural logarithm of 10 | Constants.Math.ln10 |

Chemistry

| Symbol | Definition | Accessor | |--------------|-------------------------------------------------|-----------------------------| | NA | Avogadro's number (1/mol) | Constants.Chemistry.N_A | | R | Gas constant (J/(mol·K)) | Constants.Chemistry.R | | k | Boltzmann constant (J/K) | Constants.Chemistry.k | | F | Faraday constant (C/mol) | Constants.Chemistry.F | | Vm | Molar volume of an ideal gas at STP (m³/mol) | Constants.Chemistry.V_m | | ∆Hf | Standard enthalpy of formation for water (kJ/mol) | Constants.Chemistry.deltaH_f |

License

This project is licensed under the MIT License.