Answers begin here
Change directory
Ghost together
Special edition
ghost sitting
ghost sitting

Server Restarted

Hmm...looks like the server was just restarted because new features were added or something else was updated.
Asked Jul/27/2023 ago
Modified Aug/5/2023 ago
Viewed 0 times
0 answers
Can you help improve this post? Post a detailed answer to this question, Make sure to include references or provide extras that justify why your answer is accurate. Brief or insufficient answers may be subjected to edits or removal.

What is the purpose of the "yield" keyword in Python, and how does it work?

I'm trying to grasp the concept of the "yield" keyword in Python by analyzing the following code snippet:

def _get_similar_candidates(self, similarity, min_similarity, max_similarity):
    if self._left_child and similarity - max_similarity < self._median:
        yield self._left_child
    if self._right_child and similarity + max_similarity >= self._median:
        yield self._right_child

This code is part of a larger program where there's a method called _get_similar_candidates defined within a class. The purpose of this method is to identify and return candidate nodes that meet certain similarity criteria based on the given input parameters similarity, min_similarity, and max_similarity.

Now, the caller code looks like this:

result, candidates = [], [self]
while candidates:
    node = candidates.pop()
    similarity = node._get_similarity(target_object)
    if min_similarity <= similarity <= max_similarity:
    candidates.extend(node._get_similar_candidates(similarity, min_similarity, max_similarity))
return result

In this caller code, an initial list called candidates is created with the current object self as its single element. The code then enters a loop, where it repeatedly pops elements from the candidates list and examines their similarity to the target_object. If the similarity of a node falls within the specified range (min_similarity and max_similarity), the node's values are added to the result list.

Now, let's focus on the critical part of this process - the _get_similar_candidates method. When this method is called, it performs some checks on its own node (self) to determine whether it satisfies the similarity conditions based on the given similarity, min_similarity, and max_similarity values. If a certain condition is met, the method utilizes the yield keyword to create an iterator and yield the left child and/or right child nodes as candidate results.

Here's how it works:

The method checks if the left child exists self._left_child. If it does and meets the similarity criteria, it yields the left child as a candidate.

Similarly, the method checks if the right child exists self._right_child. If it does and meets the similarity criteria, it yields the right child as another candidate.

By using the yield keyword, the _get_similar_candidates method creates a generator function, which means that it doesn't return an ordinary list containing the candidate nodes. Instead, it returns an iterator that generates candidate nodes one by one, as they are needed. This makes it memory-efficient as it doesn't create a large list all at once.

The caller code iterates through this generator and extends the candidates list with the yielded candidate nodes. The loop continues until all nodes that satisfy the similarity conditions have been processed. Each time the method is called again, it picks up from where it left off, allowing the iteration to continue until there are no more candidate nodes to yield.

So, to summarize, the _get_similar_candidates method returns a generator that yields candidate nodes meeting the specified similarity conditions. The method is called repeatedly until all eligible candidates are processed, and subsequent calls stop once there are no more candidates left to yield.
pythonyieldselfsimilarityexampleexplainedSave Post
Cancel editing post
Asked 27 Jul 2023 21:33
Ghost Together
Use comments to ask for more information or to suggest improvements to the question. Avoid answering questions in the comments. If you have an accurate answer, it's best to post an answer instead. Ghost Together 28 Jul 2023 04:47 AM
Enter at least 10 characters...Cancel
Enter at least 10 characters...Cancel
0 Answers / be the first to answer this question!
Post Your Answer
Enter at least 10 characters...Cancel
Unlock ability to Post Answers by registering for your free account. You need to register or login to add an answer to this question. Register and click on verification code link in your email inbox to log in.
Try to answer the actual question being asked, and not just post related information. Be sure to provide an accurate answer. The more accurate your answer is the more people your response will help in the future.
Post Answer
We are grateful for your contribution to Ghost Overflow!
  • Please be sure to read the question to understand it and answer the question that was asked. Be as detailed as possible in sharing your answer.
Things to avoid...
  • Asking for help, clarification, or responding to other answers.
  • Making statements based on opinion; back them up with references or personal experience.
We're currently editing our tips on writing great answers, soon to be posted here...
You need to log in to answer this post...
Ghost Together
Hotel Overlook
Almost not here...
Greg Sometimes
Just another status...
Greg Sometimes
Just another status...
Greg Sometimes
Just another status...
Greg Sometimes
Just another status...
Greg Sometimes
Just another status...
OFFLINE - 34,125
Create New Post
Safari Logo SVG
To install Ghost Messenger on your IOS open it in Safari and Add it to Home Screen
Click on feather button to post your first message!