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Re95: The PriorityQueue Class, Part E (Best-First-Search Part 14, AIMA4e pp. 73-74)

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frontier is a PriorityQueue which is built on heapq and uses f to create (score, item) pairs to be queued. Printing verbose updates as BFS proceeds, using PriorityQueue, from A to B, including calculating straight-line distances as a heuristic (f1); the frontier list (PriorityQueue) and reacheddictionary can be seen growing; the selection of nodes from children is based on the ordering of the frontier PriorityQueueusing f1, the evaluation function.

Air date: Monday, 26th Dec. 2022, 10:00 PM Eastern/US.

Getting from A to B ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

PIC Getting from A to B by way of S and F. A question raised during the livestream: Why do the straight-line distances not match the http://aima.cs.berkeley.edu/figures.pdf graph (Figure 3.1)? Straight line distances are not road distances; the graph represents road distances, confusingly, as straight lines. ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

PIC Source code. A question raised during the livestream: Why is the lenmethod called before the first whileloop printstatement? The while frontier:test is run at line 123, which seems to call the len method. ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Other sources to consult: * https://docs.python.org/3/library/pdb.html * Russell & Norvig (2020); * Retraice (2022/12/14); * Retraice (2022/12/15); * Retraice (2022/12/16); * Retraice (2022/12/17); * Retraice (2022/12/18); * Retraice (2022/12/19); * Retraice (2022/12/20); * Retraice (2022/12/21); * Retraice (2022/12/22a); * Retraice (2022/12/22b); * Retraice (2022/12/23); * Retraice (2022/12/24); * Retraice (2022/12/25); * http://aima.cs.berkeley.edu/figures.pdf; * https://github.com/aimacode/aima-python/blob/master/search4e.ipynb; * https://github.com/retraice/ReAIMA4e/.

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References

Retraice (2022/12/14). Re82: What is a problem? (BEST-FIRST-SEARCH Part 1, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re82Retrieved 15th Dec. 2022.

Retraice (2022/12/15). Re83: A Problem Instantiated (BEST-FIRST-SEARCH Part 2, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re83Retrieved 16th Dec. 2022.

Retraice (2022/12/16). Re84: A Node Instantiated (BEST-FIRST-SEARCH Part 3, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re84Retrieved 17th Dec. 2022.

Retraice (2022/12/17). Re85: The Details (BEST-FIRST-SEARCH Part 4, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re85Retrieved 18th Dec. 2022.

Retraice (2022/12/18). Re86: Code Reading (BEST-FIRST-SEARCH Part 5, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re86Retrieved 19th Dec. 2022.

Retraice (2022/12/19). Re87: The multimap Function, Part A (BEST-FIRST-SEARCH Part 6, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re87Retrieved 20th Dec. 2022.

Retraice (2022/12/20). Re88: The multimap Function, Part B (BEST-FIRST-SEARCH Part 7, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re88Retrieved 21st Dec. 2022.

Retraice (2022/12/21). Re89: The multimap Function, Part C (BEST-FIRST-SEARCH Part 8, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re89Retrieved 22nd Dec. 2022.

Retraice (2022/12/22a). Re90: The Map Class (BEST-FIRST-SEARCH Part 9, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re90Retrieved 23rd Dec. 2022.

Retraice (2022/12/22b). Re91: The PriorityQueue Class, Part A (BEST-FIRST-SEARCH Part 10, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re91Retrieved 24th Dec. 2022.

Retraice (2022/12/23). Re92: The PriorityQueue Class, Part B (BEST-FIRST-SEARCH Part 11, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re92Retrieved 24th Dec. 2022.

Retraice (2022/12/24). Re93: The PriorityQueue Class, Part C (BEST-FIRST-SEARCH Part 12, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re93Retrieved 25th Dec. 2022.

Retraice (2022/12/25). Re94: The PriorityQueue Class, Part D (BEST-FIRST-SEARCH Part 13, AIMA4e pp. 73-74). retraice.com. https://www.retraice.com/segments/re94Retrieved 26th Dec. 2022.

Russell, S., & Norvig, P. (2020). Artificial Intelligence: A Modern Approach. Pearson, 4th ed. ISBN: 978-0134610993. Searches: https://www.amazon.com/s?k=978-0134610993 https://www.google.com/search?q=isbn+978-0134610993 https://lccn.loc.gov/2019047498