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Python notes Object oriented - inheritance I Introduction to inheritance Inheritance Encyclopedia Python object-oriented inheritance refers to the ownership relationship between multiple classes, that is, the subclass inherits all the properties and methods of the parent class by default. In Python, all classes inherit the ...

Daily test 1,Three characteristics of elements in a set Must be of immutable type disorder No repetition 2,What is the purpose of the collection? Relational operation duplicate removal 3,An example is given to illustrate the relational operation intersection s1 & s2 Union s1 | s2 Differen ...

preface Data structure is the way that computer stores and organizes data. A data structure is a collection of data elements that have one or more specific relationships with each other. In general, carefully selected data structures can bring higher operation or storage efficiency. Data structure is often related to efficient retrieval al ...

The essence of a computer is calculation. Internally, it is the change of bits of 0 and 1, and externally, it is the change of data. So what data can computers process? In essence, data is stored in bytes. In terms of performance, they are integers, floating-point numbers, strings and so on. Python's basic data types are no more than this. I ...

Import numpy and view version import numpy as np np.__version__ '1.13.1' What is numpy? That is, Numeric Python. After expansion, python can support array and matrix types, including a large number of matrix and array calculation functions Numpy framework is the basis of machine learning and data mining. pandas, scipy and matplotli ...

Latest features of Cartopy 0.20 Background introduction Cartopy is a map mapping package developed by the Met Office, which realizes most of the functions of Basemap and makes use of the powerful proj 4. NumPy and Shapely libraries, and a programming interface is built on Matplotlib to create and publish quality maps, and conduct geospatial d ...

For Python 2.1 and later versions, unittest is put into the python development package as a standard module. 01 use unittest to write test cases [at the end of the paper, a learning resource for automated testing is prepared for free sharing] Rules: import unittestTo create a test class, you must inherit unittest Testcase classCreate a test ...

Catalogue 1. Usage scenario of queue class 2. queue class 2.1. queue class constructor 2.2 queue class attributes and methods 3. queue.Queue usage scenario 3.1 creating queues 3.2 use the methods of empty(), full(), qsize() to check the queue status 3.3 use put(), put_ The nowait () method is inserted into the queue 3.4 using get(), ge ...

What is a tuple Tuple is a data type similar to list and. They have basically the same characteristics, but they also have many differences. Tuples, like lists, are queues that can store multiple data structuresThe same tuple is also an ordered set with repeatable elements Definition and creation of tuples In Python, tuple represents th ...

What is a list List is a very important data type in Python. Why is it so important? Because in our actual development process, list is a data structure that is often used. It is widely used because it takes up less space and wastes less memory space. A list is a queueIt is not only a collection of various data, but also a data structureA ...