TS Calculator

Library that makes possible evaluating math expressions with functions, constants and radix numbers easily, and 100% safe

-- Feel free with making feature suggestions and open issues if you find a bug!

Installation

$ npm install @luminate_d/tscalculator

Usage

import { Lexer, Parser, CalculatorError } from '@luminate_d/tscalculator';

const input = 'cos(pi) * 0xff + 2^8'; // Your expression

try {
  const expression = new Parser(
          new Lexer(input).tokenize()
  ).parse();

  const result = expression.eval(); // 1
  console.log('Result:', result);
} catch(error: CalculatorError) {
  if(error instanceof RuntimeError) {
    console.log('Failed to eval:', error.message);
  } else console.log('Error at character index', error.index);
}

Adding custom constants/functions

import { Constants, Functions } from '@luminate_d/tscalculator';

Constants.register('name', 1000);
Functions.register('name', (num: number) => (0xff % num) ^ 8);

Errors

• UnknownConstantError / UnknownFunctionError occurs when unknown name provided
• ParseError occurs when invalid expression provided and it cannot be parsed
  • Has .index property that shows index of character where error occurred

Available constants

• PI, E, EPI (e^pi), LN2, LN10, LOG2E, LOG10E, PHI, PSI, P

Available functions

• sin
• cos
• tg, tan
• ctg, cotan
• sec, sc
• csc, cosec
• sinh
• cosh
• th, tanh
• cth, coth
• sech, sch
• csch, cosech
• asin
• acos
• asinh
• acosh
• versin
• exp
• gd
• floor
• ceil
• round
• abs
• sqrt
• crt
• cbrt
• ln
• log - can be called like log(100, 10) - log 100 by base 10, defaults base to E
• tetrate
• rad - degrees to radians
• deg - radians to degrees
• log2
• log10
• log1p
• digits - calculate how many digits are present in number digits(18293) = 5
• trunc
• random

Syntax

• Constant: pi or PI - Case insensitive, name of any constant, will be replaced by its value
• Add: x + y: x/y = constant or number (or function expression sin(x) + y)
• Subtract: x - y
• Multiply: x * y
• Divide: x / y
• Power: x ^ y
• Mod: x % y
• Function: sin(x)
• Factor: x!
• Double Factor: x!!
• Subfactor: !x
• Radix Numbers:
  • 0b10 - Binary (0b) representation of 2
  • 0o15 - Octal (0o) representation of 13
  • 0xff - Binary (0x) representation of 255