股票（stock），是股份公司发行的所有权凭证，是股份公司为筹集资金而发行给各个股东作为持股凭证并借以取得股息和红利的一种有价证券。每股股票都代表股东对企业拥有一个基本单位的所有权。每家上市公司都会发行股票。
同一类别的每一份股票所代表的公司所有权是相等的。每个股东所拥有的公司所有权份额的大小，取决于其持有的股票数量占公司总股本的比重。
股票是股份公司资本的构成部分，可以转让、买卖，是资本市场的主要长期信用工具，但不能要求公司返还其出资。
Reference links:
(. 1) on BP algorithm of the neural network (FIG said neural network algorithm theoretical derivation on BP + + + examples use the code)
https://blog.csdn.net/weixin_39441762/article/details/80446692
(2) neural network and BP C and python code
https://blog.csdn.net/u014403897/article/details/46409531
(3) the neural network theory and implementation of Python BP algorithm source code parsing
https://www.jianshu.com/p/679e390f24bb
(4) machine learning algorithm basis --BP
https://blog.csdn.net/g11d111/article/details/70943463
(5) a text thoroughly get to know the BP algorithm: the principle of derivation + + project combat data presentation (Part I)
https://blog.csdn.net/fendouaini/article/details/79789440
(6) vernacular to explain the BP algorithm
https://blog.csdn.net/zhaomengszu/article/details/77834845
(7) yourself achieve machine-learning algorithms: neural networks (with source code)
https://blog.csdn.net/zhouzx2010/article/details/71126800/
(8) -matlab achieve stock forecasting model for BP neural network based on genetic algorithms
https://blog.csdn.net/zxm_jimin/article/details/87936920
https://download.csdn.net/download/zxm_jimin/10976678
(9) using a neural network prediction closing stock price (source code included)
https://www.cnblogs.com/yunerlalala/p/6187770.html
(10) BP neural network prediction data (source code attached Engineering)
https://blog.csdn.net/ETERNITY_neu/article/details/85340305
(11) using MATLAB 2016a prediction neural network BP (containing Neural Network Toolbox)
https://blog.csdn.net/y1535766478/article/details/79607165
(12) BP neural network to predict population program (matlab realize)
https://blog.csdn.net/weixin_42296976/article/details/81146746
(13) shares of BP neural network to predict
https://blog.csdn.net/u010076558/article/details/12773679