@technobuddha/library/ordinal/ordinal.mjs

A large library of useful functions

import isNaN from 'lodash/isNaN';
import isInteger from 'lodash/isInteger';
//const ones      = [ 'zero', 'first', 'second', 'third', 'fourth', 'fifth', 'sixth', 'seventh', 'eighth', 'ninth',
//                  'tenth', 'eleventh', 'twelfth', 'thirteenth', 'fourteenth', 'fifteenth', 'sixteenth', 'seventeenth', 'eighteenth', 'nineteenth' ];
//const tens      = [ 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety' ];
// twentieth thirtieth fortieth fiftieth sixtieth seventieth eightieth ninetieth
// hundredth
// thousandth
// millionth
// TODO [2021-09-30] this needs an overhaul and some documentation
/**
 * Convert a number into an ordinal number string (1st, 2nd, 3rd, etc).
 * @param input    The number to convert
 */
export function ordinal(input) {
    if (isNaN(input)) {
        return input.toString();
    }
    else if (isInteger(input)) {
        switch (Math.abs(input) % 100) {
            case 1:
            case 21:
            case 31:
            case 41:
            case 51:
            case 61:
            case 71:
            case 81:
            case 91:
                return `${input.toString()}st`;
            case 2:
            case 22:
            case 32:
            case 42:
            case 52:
            case 62:
            case 72:
            case 82:
            case 92:
                return `${input.toString()}nd`;
            case 3:
            case 23:
            case 33:
            case 43:
            case 53:
            case 63:
            case 73:
            case 83:
            case 93:
                return `${input.toString()}rd`;
            default:
                return `${input.toString()}th`;
        }
    }
    else {
        return `${input.toString()}th`;
    }
}
export default ordinal;