Function isDom

libs/echarts/echarts.simple.js:723–727

* @memberOf module:zrender/core/util * @param {*} value * @return {boolean}

(value)

 * @return {boolean}
 */
function isDom(value) {
    return typeof value === 'object'
        && typeof value.nodeType === 'number'
        && typeof value.ownerDocument === 'object';
}

/**
 * Whether is exactly NaN. Notice isNaN('a') returns true.