ZPTCON - Online Linux Manual Page

Section : 1
Updated : November 2008
Source : LAPACK routine (version 3.2)
Note : LAPACK routine (version 3.2)

NAMEZPTCON - computes the reciprocal of the condition number (in the 1-norm) of a complex Hermitian positive definite tridiagonal matrix using the factorization A = L*D*L**H or A = U**H*D*U computed by ZPTTRF

SYNOPSISSUBROUTINE ZPTCON(  N, D, E, ANORM, RCOND, RWORK, INFO )  INTEGER INFO, N  DOUBLE PRECISION ANORM, RCOND  DOUBLE PRECISION D( * ), RWORK( * )  COMPLEX*16 E( * )

PURPOSEZPTCON computes the reciprocal of the condition number (in the 1-norm) of a complex Hermitian positive definite tridiagonal matrix using the factorization A = L*D*L**H or A = U**H*D*U computed by ZPTTRF. Norm(inv(A)) is computed by a direct method, and the reciprocal of the condition number is computed as

                 RCOND = 1 / (ANORM * norm(inv(A))).

ARGUMENTSN (input) INTEGER  The order of the matrix A. N >= 0. D (input) DOUBLE PRECISION array, dimension (N)  The n diagonal elements of the diagonal matrix D from the factorization of A, as computed by ZPTTRF. E (input) COMPLEX*16 array, dimension (N-1)  The (n-1) off-diagonal elements of the unit bidiagonal factor U or L from the factorization of A, as computed by ZPTTRF. ANORM (input) DOUBLE PRECISION  The 1-norm of the original matrix A. RCOND (output) DOUBLE PRECISION  The reciprocal of the condition number of the matrix A, computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is the 1-norm of inv(A) computed in this routine. RWORK (workspace) DOUBLE PRECISION array, dimension (N)  INFO (output) INTEGER  = 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value

FURTHER DETAILSThe method used is described in Nicholas J. Higham, "Efficient Algorithms for Computing the Condition Number of a Tridiagonal Matrix", SIAM J. Sci. Stat. Comput., Vol. 7, No. 1, January 1986.
0
Johanes Gumabo
Data Size   :   7,534 byte
man-zptcon.lBuild   :   2025-03-22, 13:26   :  
Visitor Screen   :   x
Visitor Counter ( page / site )   :   1 / 1,209,319
Visitor ID   :     :  
Visitor IP   :   3.135.248.130   :  
Visitor Provider   :   AMAZON-02   :  
Provider Position ( lat x lon )   :   37.751000 x -97.822000   :   x
Provider Accuracy Radius ( km )   :   1000   :  
Provider City   :     :  
Provider Province   :   ,   :   ,
Provider Country   :   United States   :  
Provider Continent   :   North America   :  
Visitor Recorder   :   Version   :  
Visitor Recorder   :   Library   :  
Online Linux Manual Page   :   Version   :   Online Linux Manual Page - Fedora.40 - march=x86-64 - mtune=generic - 25.03.22
Online Linux Manual Page   :   Library   :   lib_c - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Online Linux Manual Page   :   Library   :   lib_m - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Data Base   :   Version   :   Online Linux Manual Page Database - 24.04.13 - march=x86-64 - mtune=generic - fedora-38
Data Base   :   Library   :   lib_c - 23.02.07 - march=x86-64 - mtune=generic - fedora.36


Very long time ago, I have the best tutor, Wenzel Svojanovsky. If someone knows the email address of Wenzel Svojanovsky, please send an email to johanesgumabo@gmail.com.
Help me, linux0001.com will expire on July 16, 2025. I have no money to renew it. View detail

If error, please print screen and send to johanes_gumabo@yahoo.co.id
Under development. Support me via PayPal.