I keep seeing "bootstrapping" mentioned in discussions of application development. It seems both widespread and important, but I've yet to come across even a poor explanation of what bootstrapping actually is; rather, it seems as though everyone is just supposed to know what it means. I don't, though. Near as I can figure, it has something to do with initialization tasks required of an application upon launch, but I could be completely wrong about that. Can anyone help me to understand this idea?


当前回答

“Bootstrapping”来源于“靠自己的力量把自己拉起来”这个词。这些你可以从维基百科上得到。

在计算中,引导加载程序是机器启动时运行的第一段代码,负责加载操作系统的其余部分。在现代计算机中,它存储在ROM中,但我记得PDP-11上的引导过程,你可以通过前面板开关插入位来将特定的磁盘段加载到内存中,然后运行它。不用说,引导加载程序通常非常小。

“Bootstrapping”也被用作一个术语,用于构建一个使用自身的系统——或者更准确地说,是一个前身版本。例如,ANTLR版本3使用在ANTLR版本2中开发的解析器编写。

其他回答

在一些web框架中有一个引导的例子。你调用index.php (bootstrapper),然后它加载框架的助手、模型、配置,然后加载控制器并将控制权传递给它。

正如您所看到的,这是一个启动大进程的简单文件。

除了它在软件开发中的应用(例如kdgregory给出的答案)和Dirk Eddelbuettel所讨论的在统计学中的应用之外,在强化学习的上下文中,Bootstrapping还有另一个对开发人员有用的含义。

来自萨顿和巴托:

Widrow, Gupta, and Maitra (1973) modified the Least-Mean-Square (LMS) algorithm of Widrow and Hoff (1960) to produce a reinforcement learning rule that could learn from success and failure signals instead of from training examples. They called this form of learning “selective bootstrap adaptation” and described it as “learning with a critic” instead of “learning with a teacher.” They analyzed this rule and showed how it could learn to play blackjack. This was an isolated foray into reinforcement learning by Widrow, whose contributions to supervised learning were much more influential.

这本书描述了各种强化算法,其中目标值是基于先前的近似作为bootstrap方法:

最后,我们注意到 DP[动态规划]方法的最后一个特殊性质。所有这些都更新了估计 基于对继承者价值的估计的状态值 州。也就是说,他们在其他数据的基础上更新估计 估计。我们把这叫做引导。许多钢筋 学习方法执行引导,即使是那些没有引导的方法 要求,正如DP要求,一个完整和准确的模型 环境。

请注意,这不同于维基百科页面上提到的自举聚合和智能爆炸。

引导文件负责加载主文件的内容。它是主文件的包装器。这样,如果由于某种原因加载文件不成功,我们就可以捕获错误。

I belong to the generation who flipped switches to enter a boot program. In the early 1980s, I worked on a microcomputer called Micro-78, developed by Electronics Corporation of India Ltd (ECIL). It was a sort of clone of Altair 8800. I distinctly remember what happens when a small boot program was entered using the toggle switches and executed by pressing a button. The program reads a second boot program contained in the 1st track of the floppy disk and overwrites it on itself in such a way that the second boot program starts executing to load a disk operating system. I think the term "bootstrap" refers to this process of the first boot program reading and overwriting the second boot program on itself, in a way "pulling itself up" with the additional functionality of the second boot program. That may be the origin of the original meaning of "the bootstrap program".

在应用程序开发的上下文中,“引导”通常在讨论模块化和/或自动更新软件时出现。

而不是用户下载整个应用程序,包括他不需要的功能,并重新下载和手动更新它,只要有更新,用户只下载和启动一个小的“引导”可执行文件,它反过来下载和安装用户需要的应用程序的那些部分。此外,引导组件能够在每次启动时查找更新并安装它们。

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