Maple Professional
Maple Academic
Maple Student Edition
Maple Personal Edition
Maple Player
Maple Player for iPad
MapleSim Professional
MapleSim Academic
Maple T.A. - Testing & Assessment
Maple T.A. MAA Placement Test Suite
Möbius - Online Courseware
Machine Design / Industrial Automation
Aerospace
Vehicle Engineering
Robotics
Power Industries
System Simulation and Analysis
Model development for HIL
Plant Modeling for Control Design
Robotics/Motion Control/Mechatronics
Other Application Areas
Mathematics Education
Engineering Education
High Schools & Two-Year Colleges
Testing & Assessment
Students
Financial Modeling
Operations Research
High Performance Computing
Physics
Live Webinars
Recorded Webinars
Upcoming Events
MaplePrimes
Maplesoft Blog
Maplesoft Membership
Maple Ambassador Program
MapleCloud
Technical Whitepapers
E-Mail Newsletters
Maple Books
Math Matters
Application Center
MapleSim Model Gallery
User Case Studies
Exploring Engineering Fundamentals
Teaching Concepts with Maple
Maplesoft Welcome Center
Teacher Resource Center
Student Help Center
Matlab[qr] - compute the QR orthogonal-triangular decomposition of a MapleMatrix or MatlabMatrix in MATLAB(R), where X*P = Q*R
Calling Sequence
qr(X, output=R)
qr(X, output=QR)
qr(X, output=QRP)
Parameters
X
-
MapleMatrix or MatlabMatrix
output
specify the form of the output (optional)
R
return the upper triangular matrix R
QR
return unitary matrix Q and upper triangular R matrix
QRP
return Q, R, and permutation matrix P
Description
The qr command computes the QR orthogonal-triangular decomposition of a matrix (either a Maple matrix or a MatlabMatrix) in MATLAB. When output=QRP, the result is computed where . When output=QR, the result is computed where .
The matrix X can be either square or rectangular.
The matrix X is expressed as product of an upper triangular matrix and either a real orthonormal matrix or a complex unitary matrix.
The default if no output option is specified is to return the matrices Q and R.
Examples
Define the Maple matrix
The QR decomposition of this MapleMatrix is computed and returns Q and R, as follows:
Q, R :=
[-0.404519917477945468 , 0.418121005003545431 , -0.120768607347027060 , -0.804334137667873206]
[-0.134839972492648424 , -0.903141370807658106 , 0.0315048540905287777 , -0.406400406400609482]
[-0.809039834955890602 , -0.0836242010007090253 , -0.399061485146697980 , 0.423333756667301608]
[-0.404519917477945301 , 0.0501745206004254873 , 0.908389959610246600 , 0.0931334264668064182]
[-7.41619848709566209 -8.09039834955890668 -11.0568777443971715]
[ ]
[ 0. -5.43557306504609006 -2.67597443202269013]
[ 0. 0. 2.92995143041917760 ]
[ 0. 0. 0. ]
The QR decomposition returning only the R matrix is as follows:
[-7.41619848709566209 , -8.09039834955890668 , -11.0568777443971715]
[0.0960043149368622339 , -5.43557306504609006 , -2.67597443202269013]
[0.576025889621173404 , 0.166971439413840017 , 2.92995143041917760]
[0.288012944810586701 , 0.0361500352119390120 , -0.704436674263540508]
To force the lower triangle entries to zero, use
Note that the R in is surrounded by quotation marks, since the variable R was assigned previously. QR decomposition returning Q, R, and P matrices is as follows:
See Also
LinearAlgebra[QRDecomposition], Matlab, Matlab[chol], Matlab[det], Matlab[evalM], Matlab[inv], Matlab[lu], MatlabMatrix
Download Help Document