Rectangular Matrix LU Decomposition: Difference between revisions

From Algorithm Wiki
Jump to navigation Jump to search
(Created page with "{{DISPLAYTITLE:Rectangular Matrix LU Decomposition (LU Decomposition)}} == Description == Lower–upper (LU) decomposition or factorization factors a matrix as the product of a lower triangular matrix and an upper triangular matrix. In the general case, the input is an $m \times n$ matrix. == Related Problems == Subproblem: Square Matrix LU Decomposition == Parameters == <pre>$m$: number of rows in input matrix $n$: number of columns in input matrix $l$: numb...")
 
No edit summary
Line 10: Line 10:
== Parameters ==  
== Parameters ==  


<pre>$m$: number of rows in input matrix
$m$: number of rows in input matrix
 
$n$: number of columns in input matrix
$n$: number of columns in input matrix
$l$: number of columns chosen to use in the decomposition ($l \geq k$)
$l$: number of columns chosen to use in the decomposition ($l \geq k$)
$k$: desired rank of decomposition</pre>
 
$k$: desired rank of decomposition


== Table of Algorithms ==  
== Table of Algorithms ==  

Revision as of 12:02, 15 February 2023

Description

Lower–upper (LU) decomposition or factorization factors a matrix as the product of a lower triangular matrix and an upper triangular matrix. In the general case, the input is an $m \times n$ matrix.

Related Problems

Subproblem: Square Matrix LU Decomposition

Parameters

$m$: number of rows in input matrix

$n$: number of columns in input matrix

$l$: number of columns chosen to use in the decomposition ($l \geq k$)

$k$: desired rank of decomposition

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Closed formula 1975 $O(nlogn)$ Exact Deterministic
Randomized LU Decomposition 2016 $O(n^{3})$ $\tilde{O}(nl + ml)$ See Theorem 4.3 in original paper for error bound Randomized Time
David 2006 $O(nlogn)$ Exact Deterministic