CFG Parsing: Difference between revisions

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(Created page with "{{DISPLAYTITLE:CFG Parsing (CFG Problems)}} == Description == Given a grammar $G$ and a string $s$, find the parse structure, or analysis, assigned to the string $s$ by the grammar $G$. == Related Problems == Related: CFG Recognition == Parameters == <pre>n: length of the given string</pre> == Table of Algorithms == {| class="wikitable sortable" style="text-align:center;" width="100%" ! Name !! Year !! Time !! Space !! Approximation Factor !! Model !! Re...")
 
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== Parameters ==  
== Parameters ==  


<pre>n: length of the given string</pre>
$n$: length of the given string
 
$|G|$: size of the grammar


== Table of Algorithms ==  
== Table of Algorithms ==  
Line 22: Line 24:
| [[Earley parser (CFG Parsing CFG Problems)|Earley parser]] || 1968 || $O(n^{3})$ || $O(n^{2})$ || Exact || Deterministic || [https://web.archive.org/web/20040708052627/http://www-2.cs.cmu.edu/afs/cs.cmu.edu/project/cmt-55/lti/Courses/711/Class-notes/p94-earley.pdf Time & Space]
| [[Earley parser (CFG Parsing CFG Problems)|Earley parser]] || 1968 || $O(n^{3})$ || $O(n^{2})$ || Exact || Deterministic || [https://web.archive.org/web/20040708052627/http://www-2.cs.cmu.edu/afs/cs.cmu.edu/project/cmt-55/lti/Courses/711/Class-notes/p94-earley.pdf Time & Space]
|-
|-
| [[GLR parser (CFG Parsing CFG Problems)|GLR parser]] || 1974 || $O(n^{3})$ || $O(n^{3})$ || Exact || Deterministic || [https://link-springer-com.ezproxy.canberra.edu.au/chapter/10.1007%2F978-3-662-21545-6_18 Time] & [https://link-springer-com.ezproxy.canberra.edu.au/content/pdf/10.1007/978-3-662-21545-6.pdf Space]
| [[GLR parser (CFG Parsing CFG Problems)|GLR parser]] || 1974 || $O(n^{3})$ || $O(n^{3})$ || Exact || Deterministic || [https://link-springer-com.ezproxy.canberra.edu.au/chapter/10.1007%2F978-3-662-21545-6_18 Time & Space]
|-
|-
|}
|}


== Time Complexity graph ==  
== Time Complexity Graph ==  


[[File:CFG Problems - CFG Parsing - Time.png|1000px]]
[[File:CFG Problems - CFG Parsing - Time.png|1000px]]
== Space Complexity graph ==
[[File:CFG Problems - CFG Parsing - Space.png|1000px]]
== Pareto Decades graph ==
[[File:CFG Problems - CFG Parsing - Pareto Frontier.png|1000px]]


== Reductions TO Problem ==  
== Reductions TO Problem ==  

Latest revision as of 09:09, 28 April 2023

Description

Given a grammar $G$ and a string $s$, find the parse structure, or analysis, assigned to the string $s$ by the grammar $G$.

Related Problems

Related: CFG Recognition

Parameters

$n$: length of the given string

$|G|$: size of the grammar

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Earley parser 1968 $O(n^{3})$ $O(n^{2})$ Exact Deterministic Time & Space
GLR parser 1974 $O(n^{3})$ $O(n^{3})$ Exact Deterministic Time & Space

Time Complexity Graph

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Reductions TO Problem

Problem Implication Year Citation Reduction
BMM if: to-time: $O(n^{3-\epsilon})$ for some $\epsilon > {0}$ where $n \times n$ matrix
then: from-time: $O(gn^{3-\epsilon})$ where $g$ is the size of the CFG
1975 https://www-sciencedirect-com.ezproxy.canberra.edu.au/science/article/pii/S0022000075800468 link

Reductions FROM Problem

Problem Implication Year Citation Reduction
BMM if: to-time: $O(gn^{3-\epsilon})$ for some $\epsilon > {0}$ where $g$ is the size of the CFG and $n$ is the size of the string
then: from-time: $O(n^{3-\epsilon/3})$ where $n \times n$ matrix
2002 https://arxiv.org/abs/cs/0112018 link

References/Citation

https://link-springer-com.ezproxy.canberra.edu.au/chapter/10.1007%2F978-3-662-21545-6_18