* Uses `window.devicePixelRatio` if available, or CSS media queries on IE.
*
* @static
+ * @inheritable
* @return {number} Device pixel ratio
*/
$.devicePixelRatio = function () {
bits = candidate.split( / +/ );
src = bits[0];
if ( bits.length > 1 && bits[1].charAt( bits[1].length - 1 ) === 'x' ) {
- ratioStr = bits[1].substr( 0, bits[1].length - 1 );
+ ratioStr = bits[1].slice( 0, -1 );
ratio = parseFloat( ratioStr );
if ( ratio <= devicePixelRatio && ratio > selectedRatio ) {
selectedRatio = ratio;