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1 logistic growth model 1.1 J-type growth and S-type growth Exponential growth, J-shaped curve: exponential growth, that is, the growth is not restrained and explosive. For example, one person can infect three people, three people can infect nine people, and nine people can infect 27 people, which keeps doubling. This is J-type growth, ...

skip and xfail preface In actual use, it is often necessary to skip some test cases. pytest provides skip and ifskip to skip the test skip Tag in test function Usage example: @ pytest mark. Skip (reason = "the reason for skipping will be printed in the execution result"), for example 🌰: import pytest def test_1(): print(" ...

1, Reptile preparation 1.1 climbing target The target of the public comment Web crawler is the comment data of the store. The example is shown in the figure below. 1.2 web page analysis First log in, search for bubble water by keyword, and click a store at will to view all the evaluation interfaces, as shown in the figure below. First ...

python iterator and generator, decorator The iterator object is accessed from the first element of the collection until all the elements are accessed. Iterators have two basic methods: iter() and next(). String, list, or tuple objects can be used to create iterators: list1=[1,2,3] s=iter(list1) # Create iterator object print(next(s)) # The ne ...

Please don't reprint it. If you have any questions, please delete it Contact information: Q 537 four 0 six 976 Required Library Random library is to introduce random location os library to close the furnace stone legend process The multiprocessing library implements multiprocessing cv two library realizes image template matching Py autogu ...

Introduction: taking Flink 1.12 as an example, this paper introduces how to use Python language to develop Flink jobs through PyFlink API. As the most popular stream batch unified computing engine, Apache Flink is widely used in real-time ETL, event processing, data analysis, CEP, real-time machine learning and other fields. Starting from Fl ...

brief introduction The broadcast describes how NumPy calculates the operation between arrays of different shapes. If it is a larger matrix and a smaller matrix, the smaller matrix will be broadcast to ensure the correct operation. This article will explain in detail the use of broadcast in NumPy with specific examples. Basic broadcasting ...

Visualization and graph analysis of dependency parsing in natural language processing (NLP) Although the effect of dependency parsing is not as good as that of word segmentation and NER, it also has its use value. In our daily work, we have to deal with it. How to analyze the results of dependency parsing, an important aspect is its visualizat ...

How does Python store the crawled data in txt, excel and mysql respectively 1. Page analysis The page I crawled is Tencent sports, and the link is as follows: https://nba.stats.qq.com/player/list.htm **Observe the above figure: * * the left shows 30 NBA teams respectively, and the right shows the details of the corresponding players of ...

Python can detect and recognize your face from images or videos. Face detection and recognition is one of the research hotspots in the field of computer vision. The applications of face recognition include face unlocking, security protection, etc. doctors and medical staff use face recognition to obtain medical records and medical history a ...