CentOS 7.0 - man page for dpttrf (centos section 3)

Linux & Unix Commands - Search Man Pages

dpttrf.f(3) LAPACK dpttrf.f(3)NAME
dpttrf.f -
SYNOPSIS
Functions/Subroutines
subroutine dpttrf (N, D, E, INFO)
DPTTRF
Function/Subroutine Documentation
subroutine dpttrf (integerN, double precision, dimension( * )D, double precision, dimension( *
)E, integerINFO)
DPTTRF
Purpose:
DPTTRF computes the L*D*L**T factorization of a real symmetric
positive definite tridiagonal matrix A. The factorization may also
be regarded as having the form A = U**T*D*U.
Parameters:
N
N is INTEGER
The order of the matrix A. N >= 0.
D
D is DOUBLE PRECISION array, dimension (N)
On entry, the n diagonal elements of the tridiagonal matrix
A. On exit, the n diagonal elements of the diagonal matrix
D from the L*D*L**T factorization of A.
E
E is DOUBLE PRECISION array, dimension (N-1)
On entry, the (n-1) subdiagonal elements of the tridiagonal
matrix A. On exit, the (n-1) subdiagonal elements of the
unit bidiagonal factor L from the L*D*L**T factorization of A.
E can also be regarded as the superdiagonal of the unit
bidiagonal factor U from the U**T*D*U factorization of A.
INFO
INFO is 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; if k < N, the factorization could not
be completed, while if k = N, the factorization was
completed, but D(N) <= 0.
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
September 2012
Definition at line 92 of file dpttrf.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 dpttrf.f(3)