cpbtf2 man page on Scientific

Man page or keyword search:  
man Server   26626 pages
apropos Keyword Search (all sections)
Output format
Scientific logo
[printable version]

CPBTF2(1)		 LAPACK routine (version 3.2)		     CPBTF2(1)

NAME
       CPBTF2  -  computes  the	 Cholesky factorization of a complex Hermitian
       positive definite band matrix A

SYNOPSIS
       SUBROUTINE CPBTF2( UPLO, N, KD, AB, LDAB, INFO )

	   CHARACTER	  UPLO

	   INTEGER	  INFO, KD, LDAB, N

	   COMPLEX	  AB( LDAB, * )

PURPOSE
       CPBTF2 computes the Cholesky factorization of a complex Hermitian posi‐
       tive definite band matrix A.  The factorization has the form
	  A = U' * U ,	if UPLO = 'U', or
	  A = L	 * L',	if UPLO = 'L',
       where U is an upper triangular matrix, U' is the conjugate transpose of
       U, and L is lower triangular.
       This is the unblocked version of the algorithm, calling Level 2 BLAS.

ARGUMENTS
       UPLO    (input) CHARACTER*1
	       Specifies whether the upper or lower  triangular	 part  of  the
	       Hermitian matrix A is stored:
	       = 'U':  Upper triangular
	       = 'L':  Lower triangular

       N       (input) INTEGER
	       The order of the matrix A.  N >= 0.

       KD      (input) INTEGER
	       The number of super-diagonals of the matrix A if UPLO = 'U', or
	       the number of sub-diagonals if UPLO = 'L'.  KD >= 0.

       AB      (input/output) COMPLEX array, dimension (LDAB,N)
	       On entry, the upper or lower triangle  of  the  Hermitian  band
	       matrix A, stored in the first KD+1 rows of the array.  The j-th
	       column of A is stored in the j-th column of  the	 array	AB  as
	       follows:	 if  UPLO  = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-
	       kd)<=i<=j;  if  UPLO  =	'L',  AB(1+i-j,j)     =	  A(i,j)   for
	       j<=i<=min(n,j+kd).  On exit, if INFO = 0, the triangular factor
	       U or L from the Cholesky factorization A = U'*U or A = L*L'  of
	       the band matrix A, in the same storage format as A.

       LDAB    (input) INTEGER
	       The leading dimension of the array AB.  LDAB >= KD+1.

       INFO    (output) INTEGER
	       = 0: successful exit
	       < 0: if INFO = -k, the k-th argument had an illegal value
	       >  0: if INFO = k, the leading minor of order k is not positive
	       definite, and the factorization could not be completed.

FURTHER DETAILS
       The band storage scheme is illustrated by the following example, when N
       = 6, KD = 2, and UPLO = 'U':
       On entry:		       On exit:
	   *	*   a13	 a24  a35  a46	    *	 *   u13  u24  u35  u46
	   *   a12  a23	 a34  a45  a56	    *	u12  u23  u34  u45  u56
	  a11	a22  a33  a44  a55  a66	    u11	 u22  u33  u44	u55  u66 Simi‐
       larly, if UPLO = 'L' the format of A is as follows:
       On entry:		       On exit:
	  a11  a22  a33	 a44  a55  a66	   l11	l22  l33  l44  l55  l66
	  a21  a32  a43	 a54  a65   *	   l21	l32  l43  l54  l65   *
	  a31  a42  a53	 a64   *    *	   l31	l42  l53  l64	*     *	 Array
       elements marked * are not used by the routine.

 LAPACK routine (version 3.2)	 November 2008			     CPBTF2(1)
[top]

List of man pages available for Scientific

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net