org.netlib.lapack
Class Dormbr

java.lang.Object
  extended by org.netlib.lapack.Dormbr

public class Dormbr
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 * ======= * * If VECT = 'Q', DORMBR overwrites the general real M-by-N matrix C * with * SIDE = 'L' SIDE = 'R' * TRANS = 'N': Q * C C * Q * TRANS = 'T': Q**T * C C * Q**T * * If VECT = 'P', DORMBR overwrites the general real M-by-N matrix C * with * SIDE = 'L' SIDE = 'R' * TRANS = 'N': P * C C * P * TRANS = 'T': P**T * C C * P**T * * Here Q and P**T are the orthogonal matrices determined by DGEBRD when * reducing a real matrix A to bidiagonal form: A = Q * B * P**T. Q and * P**T are defined as products of elementary reflectors H(i) and G(i) * respectively. * * Let nq = m if SIDE = 'L' and nq = n if SIDE = 'R'. Thus nq is the * order of the orthogonal matrix Q or P**T that is applied. * * If VECT = 'Q', A is assumed to have been an NQ-by-K matrix: * if nq >= k, Q = H(1) H(2) . . . H(k); * if nq < k, Q = H(1) H(2) . . . H(nq-1). * * If VECT = 'P', A is assumed to have been a K-by-NQ matrix: * if k < nq, P = G(1) G(2) . . . G(k); * if k >= nq, P = G(1) G(2) . . . G(nq-1). * * Arguments * ========= * * VECT (input) CHARACTER*1 * = 'Q': apply Q or Q**T; * = 'P': apply P or P**T. * * SIDE (input) CHARACTER*1 * = 'L': apply Q, Q**T, P or P**T from the Left; * = 'R': apply Q, Q**T, P or P**T from the Right. * * TRANS (input) CHARACTER*1 * = 'N': No transpose, apply Q or P; * = 'T': Transpose, apply Q**T or P**T. * * M (input) INTEGER * The number of rows of the matrix C. M >= 0. * * N (input) INTEGER * The number of columns of the matrix C. N >= 0. * * K (input) INTEGER * If VECT = 'Q', the number of columns in the original * matrix reduced by DGEBRD. * If VECT = 'P', the number of rows in the original * matrix reduced by DGEBRD. * K >= 0. * * A (input) DOUBLE PRECISION array, dimension * (LDA,min(nq,K)) if VECT = 'Q' * (LDA,nq) if VECT = 'P' * The vectors which define the elementary reflectors H(i) and * G(i), whose products determine the matrices Q and P, as * returned by DGEBRD. * * LDA (input) INTEGER * The leading dimension of the array A. * If VECT = 'Q', LDA >= max(1,nq); * if VECT = 'P', LDA >= max(1,min(nq,K)). * * TAU (input) DOUBLE PRECISION array, dimension (min(nq,K)) * TAU(i) must contain the scalar factor of the elementary * reflector H(i) or G(i) which determines Q or P, as returned * by DGEBRD in the array argument TAUQ or TAUP. * * C (input/output) DOUBLE PRECISION array, dimension (LDC,N) * On entry, the M-by-N matrix C. * On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q * or P*C or P**T*C or C*P or C*P**T. * * LDC (input) INTEGER * The leading dimension of the array C. LDC >= max(1,M). * * WORK (workspace/output) DOUBLE PRECISION array, dimension (LWORK) * On exit, if INFO = 0, WORK(1) returns the optimal LWORK. * * LWORK (input) INTEGER * The dimension of the array WORK. * If SIDE = 'L', LWORK >= max(1,N); * if SIDE = 'R', LWORK >= max(1,M). * For optimum performance LWORK >= N*NB if SIDE = 'L', and * LWORK >= M*NB if SIDE = 'R', where NB is the optimal * blocksize. * * If LWORK = -1, then a workspace query is assumed; the routine * only calculates the optimal size of the WORK array, returns * this value as the first entry of the WORK array, and no error * message related to LWORK is issued by XERBLA. * * INFO (output) INTEGER * = 0: successful exit * < 0: if INFO = -i, the i-th argument had an illegal value * * ===================================================================== * * .. Local Scalars ..


Constructor Summary
Dormbr()
           
 
Method Summary
static void dormbr(java.lang.String vect, java.lang.String side, java.lang.String trans, int m, int n, int k, double[] a, int _a_offset, int lda, double[] tau, int _tau_offset, double[] c, int _c_offset, int Ldc, double[] work, int _work_offset, int lwork, intW info)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Dormbr

public Dormbr()
Method Detail

dormbr

public static void dormbr(java.lang.String vect,
                          java.lang.String side,
                          java.lang.String trans,
                          int m,
                          int n,
                          int k,
                          double[] a,
                          int _a_offset,
                          int lda,
                          double[] tau,
                          int _tau_offset,
                          double[] c,
                          int _c_offset,
                          int Ldc,
                          double[] work,
                          int _work_offset,
                          int lwork,
                          intW info)