ApCoCoA-1:Num.QR
From ApCoCoAWiki
(Redirected from ApCoCoA-1:Numerical.QR)
| This article is about a function from ApCoCoA-1. |
Num.QR
Computes the QR-decomposition of a matrix.
Syntax
Num.QR(A:MAT):[Q:MAT,R:MAT]
Description
Please note: The function(s) explained on this page is/are using the ApCoCoAServer. You will have to start the ApCoCoAServer in order to use it/them.
This command computes the QR-decomposition of a matrix using the external library Lapack, i.e. the matrix A will be decomposed into the product of an orthogonal matrix Q and an upper-right triangular matrix R.
@param A The matrix to decompose.
@return An orthogonal matrix Q and an upper-right triangular matrix R such that Q*R=A.
Example
Points:=Mat([[1,2,3],[2,3,4],[3,4,5]]); QR := Num.QR(Points); Dec(QR[1]*QR[2],3); -- CoCoAServer: computing Cpu Time = 0 ------------------------------- Mat([ ["0.999", "1.999", "2.999"], ["1.999", "2.999", "3.999"], ["2.999", "3.999", "4.999"] ]) -------------------------------
See also
