1. What have the authors contributed in "Optimizing unicode regular expression evaluation with previews" ?
This is indicated by the licence information on the White Rose Research Online record for the item.
read more
Optimising unicode regular expression evaluation with previews
TL;DR: A regular expression Preview is formally defined which provides a summary of all the matches possible from a given point in a regular expression in a form that can be implemented as a compact DFA and can be used to further improve the performance of the standard NFA simulation algorithm.
read more
Abstract: The jsre regular expression library was designed to provide fast matching of complex expressions over large input streams using user-selectable character encodings. An established design approach was used: a simulated non-deterministic automaton (NFA) implemented as a virtual machine, avoiding exponential cost functions in either space or time. A deterministic automaton (DFA) was chosen as a general dispatching mechanism for Unicode character classes and this also provided the opportunity to use compact DFAs in various optimization strategies. The result was the development of a regular expression Preview which provides a summary of all the matches possible from a given point in a regular expression in a form that can be implemented as a compact DFA and can be used to further improve the performance of the standard NFA simulation algorithm. This paper formally defines a preview and describes and evaluates several optimizations using this construct. They provide significant speed improvements accrued from fast scanning of anchor positions, avoiding retesting of repeated strings in unanchored searches, and efficient searching of multiple alternate expressions which in the case of keyword searching has a time complexity which is logarithmic in the number of words to be searched.
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Most frequently asked questions
Figures
Figure 1. Transitions from Basic Operations 
Figure 3. Implementation of the expression a*(a?ab|b) as a program showing the execution order for the input 'aab'. 
Figure 8. Comparative Performance of jsre with Python re on Keyword Matching 
Figure 7. Scalability of Keyword Matching 
Figure 4. jsre Virtual Machine Architecture for Regular Expression Matching 
Table 2. Execution time of basic operations.
Citations
Machine Learning Algorithm’s Measurement and Analytical Visualization of User’s Reviews for Google Play Store
Abdul Kadir Abdul Karim,Azhari Azhari,Samir Brahim Belhaouri,Ali Adil Qureshi +3 more
- 11 Aug 2020
TL;DR: It is proved that Logistic Regression gets the speed of precision, accuracy, recall, and F1 in both after preprocessing and data collection of this dataset.
Methodology for Analyzing the Traditional Algorithms Performance of User Reviews Using Machine Learning Techniques
TL;DR: It is found that logistic regression is one of the best algorithms for the review-analysis of the Google Play Store from an accuracy perspective and it is proved and demonstrated that logistics regression is better in terms of speed, rate of accuracy, recall and F1 perspective.
References
•Book
The Design and Analysis of Computer Algorithms
Alfred V. Aho,John E. Hopcroft +1 more
- 01 Jan 1974
TL;DR: This text introduces the basic data structures and programming techniques often used in efficient algorithms, and covers use of lists, push-down stacks, queues, trees, and graphs.
10.6K
Fast Pattern Matching in Strings
TL;DR: An algorithm is presented which finds all occurrences of one given string within another, in running time proportional to the sum of the lengths of the strings, showing that the set of concatenations of even palindromes, i.e., the language $\{\alpha \alpha ^R\}^*$, can be recognized in linear time.
3.4K
Finite automata and their decision problems
Michael O. Rabin,Dana Scott +1 more
TL;DR: Finite automata are considered as instruments for classifying finite tapes as well as generalizations of the notion of an automaton are introduced and their relation to the classical automata is determined.
2.1K
Programming Techniques: Regular expression search algorithm
TL;DR: A method for locating specific character strings embedded in character text is described and an implementation of this method in the form of a compiler is discussed.
1K
Bringing science to digital forensics with standardized forensic corpora
TL;DR: It is explained why corpora are needed to further forensic research, a taxonomy for describing corpora is presented, and the availability of several forensic data sets are announced.
453