function autoRound()

in src/Foundation/Theming/code/scripts/autoNumeric.js [361:471]


    function autoRound(iv, settings) { /** value to string */
        iv = (iv === '') ? '0' : iv.toString();
        convertKeyToNumber(settings, 'mDec'); /** set mDec to number needed when mDec set by 'update method */
        if (settings.mRound === 'CHF') {
            iv = (Math.round(iv * 20) / 20).toString();
        }
        var ivRounded = '',
            i = 0,
            nSign = '',
            rDec = (typeof (settings.aPad) === 'boolean' || settings.aPad === null) ? (settings.aPad ? settings.mDec : 0) : +settings.aPad;
        var truncateZeros = function (ivRounded) { /** truncate not needed zeros */
            var regex = (rDec === 0) ? (/(\.(?:\d*[1-9])?)0*$/) : rDec === 1 ? (/(\.\d(?:\d*[1-9])?)0*$/) : new RegExp('(\\.\\d{' + rDec + '}(?:\\d*[1-9])?)0*$');
            ivRounded = ivRounded.replace(regex, '$1'); /** If there are no decimal places, we don't need a decimal point at the end */
            if (rDec === 0) {
                ivRounded = ivRounded.replace(/\.$/, '');
            }
            return ivRounded;
        };
        if (iv.charAt(0) === '-') { /** Checks if the iv (input Value)is a negative value */
            nSign = '-';
            iv = iv.replace('-', ''); /** removes the negative sign will be added back later if required */
        }
        if (!iv.match(/^\d/)) { /** append a zero if first character is not a digit (then it is likely to be a dot)*/
            iv = '0' + iv;
        }
        if (nSign === '-' && +iv === 0) { /** determines if the value is zero - if zero no negative sign */
            nSign = '';
        }
        if ((+iv > 0 && settings.lZero !== 'keep') || (iv.length > 0 && settings.lZero === 'allow')) { /** trims leading zero's if needed */
            iv = iv.replace(/^0*(\d)/, '$1');
        }
        var dPos = iv.lastIndexOf('.'), /** virtual decimal position */
            vdPos = (dPos === -1) ? iv.length - 1 : dPos, /** checks decimal places to determine if rounding is required */
            cDec = (iv.length - 1) - vdPos; /** check if no rounding is required */
        if (cDec <= settings.mDec) {
            ivRounded = iv; /** check if we need to pad with zeros */
            if (cDec < rDec) {
                if (dPos === -1) {
                    ivRounded += '.';
                }
                var zeros = '000000';
                while (cDec < rDec) {
                    zeros = zeros.substring(0, rDec - cDec);
                    ivRounded += zeros;
                    cDec += zeros.length;
                }
            } else if (cDec > rDec) {
                ivRounded = truncateZeros(ivRounded);
            } else if (cDec === 0 && rDec === 0) {
                ivRounded = ivRounded.replace(/\.$/, '');
            }
            if (settings.mRound !== 'CHF') {
                return (+ivRounded === 0) ? ivRounded : nSign + ivRounded;
            }
            if (settings.mRound === 'CHF') {
                dPos = ivRounded.lastIndexOf('.');
                iv = ivRounded;
            }

        } /** rounded length of the string after rounding */
        var rLength = dPos + settings.mDec,
            tRound = +iv.charAt(rLength + 1),
            ivArray = iv.substring(0, rLength + 1).split(''),
            odd = (iv.charAt(rLength) === '.') ? (iv.charAt(rLength - 1) % 2) : (iv.charAt(rLength) % 2),
            onePass = true;
        if (odd !== 1) {
            odd = (odd === 0 && (iv.substring(rLength + 2, iv.length) > 0)) ? 1 : 0;
        }
        if ((tRound > 4 && settings.mRound === 'S') || /** Round half up symmetric */
                (tRound > 4 && settings.mRound === 'A' && nSign === '') || /** Round half up asymmetric positive values */
                (tRound > 5 && settings.mRound === 'A' && nSign === '-') || /** Round half up asymmetric negative values */
                (tRound > 5 && settings.mRound === 's') || /** Round half down symmetric */
                (tRound > 5 && settings.mRound === 'a' && nSign === '') || /** Round half down asymmetric positive values */
                (tRound > 4 && settings.mRound === 'a' && nSign === '-') || /** Round half down asymmetric negative values */
                (tRound > 5 && settings.mRound === 'B') || /** Round half even "Banker's Rounding" */
                (tRound === 5 && settings.mRound === 'B' && odd === 1) || /** Round half even "Banker's Rounding" */
                (tRound > 0 && settings.mRound === 'C' && nSign === '') || /** Round to ceiling toward positive infinite */
                (tRound > 0 && settings.mRound === 'F' && nSign === '-') || /** Round to floor toward negative infinite */
                (tRound > 0 && settings.mRound === 'U') ||
                (settings.mRound === 'CHF')) { /** round up away from zero */
            for (i = (ivArray.length - 1); i >= 0; i -= 1) { /** Round up the last digit if required, and continue until no more 9's are found */
                if (ivArray[i] !== '.') {
                    if (settings.mRound === 'CHF' && ivArray[i] <= 2 && onePass) {
                        ivArray[i] = 0;
                        onePass = false;
                        break;
                    }
                    if (settings.mRound === 'CHF' && ivArray[i] <= 7 && onePass) {
                        ivArray[i] = 5;
                        onePass = false;
                        break;
                    }
                    if (settings.mRound === 'CHF' && onePass) {
                        ivArray[i] = 10;
                        onePass = false;
                    } else {
                        ivArray[i] = +ivArray[i] + 1;
                    }
                    if (ivArray[i] < 10) {
                        break;
                    }
                    if (i > 0) {
                        ivArray[i] = '0';
                    }
                }
            }
        }
        ivArray = ivArray.slice(0, rLength + 1); /** Reconstruct the string, converting any 10's to 0's */
        ivRounded = truncateZeros(ivArray.join('')); /** return rounded value */
        return (+ivRounded === 0) ? ivRounded : nSign + ivRounded;
    }