math-base-geometry/libs/two-dimensional/Triangle.js

utils for math geometry

const utils = require("./../utils");
const handleDecimal = utils.handleDecimal;
const isNumber = utils.isNumber;
const radianToDegree = utils.radianToDegree;

function areaBaseHeight(base, height, decimalNr) {
    if (!isNumber(base) || !isNumber(height)) {
        throw "base and height should be numbers";
    }

    const formula = 1 / 2 * base * height;

    const resp = handleDecimal(formula, decimalNr);

    return resp;
}

function areaHeron(a, b, c, decimalNr) {
    if (!isNumber(a) || !isNumber(b) || !isNumber(c)) {
        throw "a, b and c should be numbers";
    }

    const sFormula = (a + b + c) / 2;

    const s = handleDecimal(sFormula, decimalNr);

    const areaFormula = Math.sqrt(s * (s - a) * (s - b) * (s - c));

    const resp = handleDecimal(areaFormula, decimalNr);

    return resp;
}

/**
 * 
 * @param {(Integer|Double)} side1 - side A|B|C of triangle
 * @param {(Integer|Double)} side2 - side A|B|C of triangle
 * @param {(Integer|Double)} angle - angle A|B|C of triangle in degree
 * @param {Bool} decimalNr - limit deciaml number
 */
function areaTwoSides(side1, side2, angle, decimalNr) {
    if (!isNumber(side1) || !isNumber(side2) || !isNumber(angle)) {
        throw "side1, side2 and angle should be numbers";
    }

    const formula = (1 / 2) * side1 * side2 * (Math.sin(radianToDegree(angle)));

    const resp = handleDecimal(formula, decimalNr);

    return resp;
}

/**
 * 
 * @param {(Integer|Double)} a
 * @param {(Integer|Double)} b
 * @param {(Integer|Double)} c
 * @param {Bool} decimalNr 
 */
function perimeter(a, b, c, decimalNr) {
    if (!isNumber(a) || !isNumber(b) || !isNumber(c)) {
        throw "a, b and c should be numbers";
    }

    const checkAB = a + b;
    const checkBC = b + c;

    if (checkAB < c) {
        throw "make sure a+b > c";
    }

    if (checkBC > a) {
        throw "make sure b+c > a";
    }

    const formula = a + b + c;

    const resp = handleDecimal(formula, decimalNr);

    return resp;
}

function base(area, side, gamma, decimalNr) {
    if (!isNumber(area) || !isNumber(side) || !isNumber(gamma)) {
        throw "area and height should be numbers";
    }

    const convertedGamma = Math.sin(radianToDegree(gamma));

    const formula = (2 * area) / (side * convertedGamma);

    const resp = handleDecimal(formula, decimalNr);

    return resp;
}

module.exports = {
    areaBaseHeight,
    areaHeron,
    areaTwoSides,
    perimeter,
    base
}