多线程的而应用场景(同时干多件事情)

多线程(三种实现方式&守护线程&礼让线程&插入线程) 多线程可以拆开理解,“多”是一个数量词,表示很多的意思,所有我们只要知道什么是线程就可以了。(1)进程:程序的基本执行实体举个例子:比如打开任务管理器,在任务管理器的第一个界面中就是进程。看下面每一个软件都对应着一个进程。所以说什么是进程?一个软件运行之后他就是一个进程,比如Typora的进程,画图板的进程。(2)线程:线程是操作系统能够就行运算调度的最小单位。它被包含在进程之中,是进程中的实际运作单位。 阅读详情

 可见,单线程确实费时间。因为单线程让CPU有了更多的闲暇时间,效率自然就低了。

100张火车票 ---5个售票点(5个线程)

最后,我用一个非常通俗的例子结束本文:

       假设一套数学练习试卷有10个题目,题目有难有易,如果第一个题目比较难,你傻傻地在那个地方死死地纠结,你很可能会卡住,此时老师又不在你身边,所以固执的你,一个题目也没有做出来,老师来了,发现你一个题目也没有做,你的效率自然就很低。这就是单线程模式,傻傻地直接往下做。如果采取多线程模式就好了,不会做,先跳过,先做容易的,等老师回来后,你再做难的,最根本的是要你处于忙碌状态,而不是死死地纠结在第一个问题上,那样,其实你没有在忙碌,你在浪费时间,效率自然就低。

使用多线程是为了提高程序运行的效率。假如有一个程序,要求用户输入多个算式,计算出结果,并分别打印到屏幕上。如果用户一直没有输入,那么无法计算,更无法打印。如果用户输入了,必须要全部输入完,才能计算出结果,再打印到屏幕。
使用线程的话,一个线程用来等待用户输入,一个用来计算结果,一个用来打印。用户在输入算式3的时候,计算线程在计算算式2,打印线程在打印算式1,三个线程同时进行,减少了等待,这样就提高了运行效率
多线程用于堆积处理,就像一个大土堆,一个推土机很慢,那么10个推土机一起来处理,当然速度就快了,不过由于位置的限制,如果20个推土机,那么推土机之间会产生相互的避让,相互摩擦,相互拥挤,反而不如10个处理的好,所以,多线程处理,线程数要开的恰当,就可以提高效率。


一个文本文件有100M,全是字符串,我要执行切分字符串,每达到N长度便执行切腹,最后求切分完成的字符串的集合

基于STM32F407ZGT6与INMP441的I2S音频采集系统:从配置到实时波形显示 本文详细介绍了基于STM32F407ZGT6与INMP441麦克风模块的I2S音频采集系统设计与实现。从硬件选型、CubeMX配置到音频数据处理和上位机波形显示,全面解析了系统架构、DMA传输优化及常见问题解决方案,帮助开发者快速构建高精度音频采集系统。 阅读详情

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深度学习工具包 DeepLearningToolbox

深度学习工具包Deprecation notice.-----This toolbox is outdated and no longer maintained.There are much better tools available for deep learning than this toolbox, e.g. [Theano](http://deeplearning.net/software/theano/), [torch](http://torch.ch/) or [tensorflow](http://www.tensorflow.org/)I would suggest you use one of the tools mentioned above rather than use this toolbox.Best, Rasmus.DeepLearnToolbox================A Matlab toolbox for Deep Learning.Deep Learning is a new subfield of machine learning that focuses on learning deep hierarchical models of data.It is inspired by the human brain's apparent deep (layered, hierarchical) architecture.A good overview of the theory of Deep Learning theory is[Learning Deep Architectures for AI](http://www.iro.umontreal.ca/~bengioy/papers/ftml_book.pdf)For a more informal introduction, see the following videos by Geoffrey Hinton and Andrew Ng.* [The Next Generation of Neural Networks](http://www.youtube.com/watch?v=AyzOUbkUf3M) (Hinton, 2007)* [Recent Developments in Deep Learning](http://www.youtube.com/watch?v=VdIURAu1-aU) (Hinton, 2010)* [Unsupervised Feature Learning and Deep Learning](http://www.youtube.com/watch?v=ZmNOAtZIgIk) (Ng, 2011)If you use this toolbox in your research please cite [Prediction as a candidate for learning deep hierarchical models of data](http://www2.imm.dtu.dk/pubdb/views/publication_details.php?id=6284)```@MASTERSTHESIS\{IMM2012-06284, author = "R. B. Palm", title = "Prediction as a candidate for learning deep hierarchical models of data", year = "2012",}```Contact: rasmusbergpalm at gmail dot comDirectories included in the toolbox-----------------------------------`NN/` - A library for Feedforward Backpropagation Neural Networks`CNN/` - A library for Convolutional Neural Networks`DBN/` - A library for Deep Belief Networks`SAE/` - A library for Stacked Auto-Encoders`CAE/` - A library for Convolutional Auto-Encoders`util/` - Utility functions used by the libraries`data/` - Data used by the examples`tests/` - unit tests to verify toolbox is workingFor references on each library check REFS.mdSetup-----1. 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