prologue generator

PHP5.5 introduces the concept of an iterative generator, the concept of iteration is already in PHP, but the iterative generator is a new feature of PHP, similar to the iterative generator in Python3, to see how the PHP5.5 Iteration Builder is defined. function xrange ($start, $end, $step = 1) {for ($i = $start; $i Yield $i;}}foreach (xrange (1, 1000000) as $num

an object to get the next elementCustom iteratorsOnce you understand the iterator protocol, you can customize the iterator.The following example implements a myrange type, which implements the __iter__ () method, which returns the object itself as an iterator object, and implements the next () method to get the next element in the container, when there is no accessible element. Throws a Stopiteration exception.　　　　classMyRange (object):def __init__(self, N): Self.idx=0 SELF.N=Ndef __iter__(self

This article mainly introduces enhanced generator in Python, namely coroutine related content, including basic syntax, usage scenarios, considerations, and similarities and differences with other language implementation.Enhanced generatorThe usage scenarios and ideas of yield and generator are described above, and only the next method of generator is used, in fac

Http://home.51.com/leiz929/diary I. What are the conditions for Parallel Running of generator sets? The whole process of putting the generator set into parallel operation is called parallel operation. Run one generator set first and send the voltage to the bus. After the other generator set is started, it should be in

This article mainly introduces the Python generator definition and simple usage, combined with the example form more detailed analysis of the Python generator concept, principles, usage and related operations considerations, the need for friends can refer to the following The examples in this article describe Python builder definitions and simple usages. Share to everyone for your reference, as follows: Fi

This article introduces the content is about PHP Generator generator Understanding, has a certain reference value, now share to everyone, the need for friends can refer to Reprinted and collated from: Send where, snow, the Corner, PHP HandbookGenerator (Generator) Issues that can be solved Quoted from official website: The

This article introduces to you about the performance of PHP in the optimization of the weapon: PHP generator of the detailed, there is a certain reference value, the need for friends can refer to, I hope you have some help. If you are a small partner in Python or other languages, you should not be unfamiliar with generators. However, many PHP developers may not know the generator, perhaps because the

In Python, all collections can be iterated, and within the Python language, iterators are used to supportFor loopBuilding and extending collection typesTraverse a text file line by rowList derivation, dictionary derivation, and set derivationTuple unpackingWhen calling a function, use the * unpacking argumentTopics covered in this chapterLanguage internal use of ITER (...) built-in functions to manipulate the way an object can be iteratedHow to implement the classic iterator pattern using Python

Before starting the course, I asked the students to fill out a questionnaire that reflected their understanding of some of the concepts in Python. Some topics ("If/else Control Flow" or "definition and use functions") are not problematic for most students. But there are a few topics where most students have little or no contact at all, especially "generator and yield keywords". I guess that's true for most novice python programmers as well. It turns

Simple generators have many advantages. In addition to being able to express the process of a class of problems in a more natural way, the generator greatly improves many inefficiencies. In Python, function calls are expensive; In addition to other factors, it takes some time to resolve the list of function arguments (in addition to other things, analyze positional and default parameters). Initialization of the frame object also takes some steps to bu

This article mainly introduces Generator and yield in Python. This article describes list derivation and Generator expressions, Fibonacci series, Generator, coroutine and yield expressions, and Generator and coroutine usage, for more information, see List derivation and generator