org.netlib.lapack
Class SGTCON
java.lang.Object
org.netlib.lapack.SGTCON
public class SGTCON
- extends java.lang.Object
SGTCON is a simplified interface to the JLAPACK routine sgtcon.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines. Using this interface also allows you
to omit offset and leading dimension arguments. However, because
of these conversions, these routines will be slower than the low
level ones. Following is the description from the original Fortran
source. Contact seymour@cs.utk.edu with any questions.
* ..
*
* Purpose
* =======
*
* SGTCON estimates the reciprocal of the condition number of a real
* tridiagonal matrix A using the LU factorization as computed by
* SGTTRF.
*
* An estimate is obtained for norm(inv(A)), and the reciprocal of the
* condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).
*
* Arguments
* =========
*
* NORM (input) CHARACTER*1
* Specifies whether the 1-norm condition number or the
* infinity-norm condition number is required:
* = '1' or 'O': 1-norm;
* = 'I': Infinity-norm.
*
* N (input) INTEGER
* The order of the matrix A. N >= 0.
*
* DL (input) REAL array, dimension (N-1)
* The (n-1) multipliers that define the matrix L from the
* LU factorization of A as computed by SGTTRF.
*
* D (input) REAL array, dimension (N)
* The n diagonal elements of the upper triangular matrix U from
* the LU factorization of A.
*
* DU (input) REAL array, dimension (N-1)
* The (n-1) elements of the first superdiagonal of U.
*
* DU2 (input) REAL array, dimension (N-2)
* The (n-2) elements of the second superdiagonal of U.
*
* IPIV (input) INTEGER array, dimension (N)
* The pivot indices; for 1 <= i <= n, row i of the matrix was
* interchanged with row IPIV(i). IPIV(i) will always be either
* i or i+1; IPIV(i) = i indicates a row interchange was not
* required.
*
* ANORM (input) REAL
* If NORM = '1' or 'O', the 1-norm of the original matrix A.
* If NORM = 'I', the infinity-norm of the original matrix A.
*
* RCOND (output) REAL
* The reciprocal of the condition number of the matrix A,
* computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an
* estimate of the 1-norm of inv(A) computed in this routine.
*
* WORK (workspace) REAL array, dimension (2*N)
*
* IWORK (workspace) INTEGER array, dimension (N)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
* .. Parameters ..
Method Summary |
static void |
SGTCON(java.lang.String norm,
int n,
float[] dl,
float[] d,
float[] du,
float[] du2,
int[] ipiv,
float anorm,
floatW rcond,
float[] work,
int[] iwork,
intW info)
|
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
SGTCON
public SGTCON()
SGTCON
public static void SGTCON(java.lang.String norm,
int n,
float[] dl,
float[] d,
float[] du,
float[] du2,
int[] ipiv,
float anorm,
floatW rcond,
float[] work,
int[] iwork,
intW info)