org.netlib.lapack
Class Dgbbrd
java.lang.Object
org.netlib.lapack.Dgbbrd
public class Dgbbrd
- extends java.lang.Object
Following is the description from the original
Fortran source. For each array argument, the Java
version will include an integer offset parameter, so
the arguments may not match the description exactly.
Contact seymour@cs.utk.edu with any questions.
* ..
*
* Purpose
* =======
*
* DGBBRD reduces a real general m-by-n band matrix A to upper
* bidiagonal form B by an orthogonal transformation: Q' * A * P = B.
*
* The routine computes B, and optionally forms Q or P', or computes
* Q'*C for a given matrix C.
*
* Arguments
* =========
*
* VECT (input) CHARACTER*1
* Specifies whether or not the matrices Q and P' are to be
* formed.
* = 'N': do not form Q or P';
* = 'Q': form Q only;
* = 'P': form P' only;
* = 'B': form both.
*
* M (input) INTEGER
* The number of rows of the matrix A. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix A. N >= 0.
*
* NCC (input) INTEGER
* The number of columns of the matrix C. NCC >= 0.
*
* KL (input) INTEGER
* The number of subdiagonals of the matrix A. KL >= 0.
*
* KU (input) INTEGER
* The number of superdiagonals of the matrix A. KU >= 0.
*
* AB (input/output) DOUBLE PRECISION array, dimension (LDAB,N)
* On entry, the m-by-n band matrix A, stored in rows 1 to
* KL+KU+1. The j-th column of A is stored in the j-th column of
* the array AB as follows:
* AB(ku+1+i-j,j) = A(i,j) for max(1,j-ku)<=i<=min(m,j+kl).
* On exit, A is overwritten by values generated during the
* reduction.
*
* LDAB (input) INTEGER
* The leading dimension of the array A. LDAB >= KL+KU+1.
*
* D (output) DOUBLE PRECISION array, dimension (min(M,N))
* The diagonal elements of the bidiagonal matrix B.
*
* E (output) DOUBLE PRECISION array, dimension (min(M,N)-1)
* The superdiagonal elements of the bidiagonal matrix B.
*
* Q (output) DOUBLE PRECISION array, dimension (LDQ,M)
* If VECT = 'Q' or 'B', the m-by-m orthogonal matrix Q.
* If VECT = 'N' or 'P', the array Q is not referenced.
*
* LDQ (input) INTEGER
* The leading dimension of the array Q.
* LDQ >= max(1,M) if VECT = 'Q' or 'B'; LDQ >= 1 otherwise.
*
* PT (output) DOUBLE PRECISION array, dimension (LDPT,N)
* If VECT = 'P' or 'B', the n-by-n orthogonal matrix P'.
* If VECT = 'N' or 'Q', the array PT is not referenced.
*
* LDPT (input) INTEGER
* The leading dimension of the array PT.
* LDPT >= max(1,N) if VECT = 'P' or 'B'; LDPT >= 1 otherwise.
*
* C (input/output) DOUBLE PRECISION array, dimension (LDC,NCC)
* On entry, an m-by-ncc matrix C.
* On exit, C is overwritten by Q'*C.
* C is not referenced if NCC = 0.
*
* LDC (input) INTEGER
* The leading dimension of the array C.
* LDC >= max(1,M) if NCC > 0; LDC >= 1 if NCC = 0.
*
* WORK (workspace) DOUBLE PRECISION array, dimension (2*max(M,N))
*
* INFO (output) INTEGER
* = 0: successful exit.
* < 0: if INFO = -i, the i-th argument had an illegal value.
*
* =====================================================================
*
* .. Parameters ..
Method Summary |
static void |
dgbbrd(java.lang.String vect,
int m,
int n,
int ncc,
int kl,
int ku,
double[] ab,
int _ab_offset,
int ldab,
double[] d,
int _d_offset,
double[] e,
int _e_offset,
double[] q,
int _q_offset,
int ldq,
double[] pt,
int _pt_offset,
int ldpt,
double[] c,
int _c_offset,
int Ldc,
double[] work,
int _work_offset,
intW info)
|
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Dgbbrd
public Dgbbrd()
dgbbrd
public static void dgbbrd(java.lang.String vect,
int m,
int n,
int ncc,
int kl,
int ku,
double[] ab,
int _ab_offset,
int ldab,
double[] d,
int _d_offset,
double[] e,
int _e_offset,
double[] q,
int _q_offset,
int ldq,
double[] pt,
int _pt_offset,
int ldpt,
double[] c,
int _c_offset,
int Ldc,
double[] work,
int _work_offset,
intW info)