不存在码 meaning in Chinese

nonexistent code

While this rule is fairly easy to follow once you know it and some ides have wizards for defining both for you in a consistent manner , if you override one of these methods and forget to override the other , this bug can be very difficult to detect through inspection - because the error is not in the code that is present , but in the code that is absent
虽然只要了解了这项规则，遵守起来就相当简单（并且有些ide包含一些向导，用于以一致的风格为您定义这两个方法），但是如果重载了其中一个方法，而忘记重载另一个方法，那么通过检测很难找出bug ，因为错误并非位于存在的代码中，而是位于不存在码中。
The goal of the filter is to improve the sensitivity of an optical receiver by optimally filtering a communication signal . in this paper we calculated the temporal response of the matched filter , the commonly used f - p filter , as well as the matched weak ofbg filter . we find that the reflected pulse of weak ofbg closely resembles the triangular shape characteristic of a perfectly matched filter
论文计算了通信系统中矩形光脉冲信号经强、弱ofbg 、匹配光滤波器、 f - p滤波器的输出光脉冲波形，经分析比较后发现：弱ofbg和理想匹配光滤波器的输出信号波形极其相似，不存在码间干扰，而f - p滤波器的输出波形存在比较严重的码间干扰。