org.netlib.lapack
Class SLAQPS

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

public class SLAQPS
extends java.lang.Object

SLAQPS is a simplified interface to the JLAPACK routine slaqps.
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 * ======= * * SLAQPS computes a step of QR factorization with column pivoting * of a real M-by-N matrix A by using Blas-3. It tries to factorize * NB columns from A starting from the row OFFSET+1, and updates all * of the matrix with Blas-3 xGEMM. * * In some cases, due to catastrophic cancellations, it cannot * factorize NB columns. Hence, the actual number of factorized * columns is returned in KB. * * Block A(1:OFFSET,1:N) is accordingly pivoted, but not factorized. * * Arguments * ========= * * 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 * * OFFSET (input) INTEGER * The number of rows of A that have been factorized in * previous steps. * * NB (input) INTEGER * The number of columns to factorize. * * KB (output) INTEGER * The number of columns actually factorized. * * A (input/output) REAL array, dimension (LDA,N) * On entry, the M-by-N matrix A. * On exit, block A(OFFSET+1:M,1:KB) is the triangular * factor obtained and block A(1:OFFSET,1:N) has been * accordingly pivoted, but no factorized. * The rest of the matrix, block A(OFFSET+1:M,KB+1:N) has * been updated. * * LDA (input) INTEGER * The leading dimension of the array A. LDA >= max(1,M). * * JPVT (input/output) INTEGER array, dimension (N) * JPVT(I) = K <==> Column K of the full matrix A has been * permuted into position I in AP. * * TAU (output) REAL array, dimension (KB) * The scalar factors of the elementary reflectors. * * VN1 (input/output) REAL array, dimension (N) * The vector with the partial column norms. * * VN2 (input/output) REAL array, dimension (N) * The vector with the exact column norms. * * AUXV (input/output) REAL array, dimension (NB) * Auxiliar vector. * * F (input/output) REAL array, dimension (LDF,NB) * Matrix F' = L*Y'*A. * * LDF (input) INTEGER * The leading dimension of the array F. LDF >= max(1,N). * * Further Details * =============== * * Based on contributions by * G. Quintana-Orti, Depto. de Informatica, Universidad Jaime I, Spain * X. Sun, Computer Science Dept., Duke University, USA * * ===================================================================== * * .. Parameters ..


Constructor Summary
SLAQPS()
           
 
Method Summary
static void SLAQPS(int m, int n, int offset, int nb, intW kb, float[][] a, int[] jpvt, float[] tau, float[] vn1, float[] vn2, float[] auxv, float[][] f)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SLAQPS

public SLAQPS()
Method Detail

SLAQPS

public static void SLAQPS(int m,
                          int n,
                          int offset,
                          int nb,
                          intW kb,
                          float[][] a,
                          int[] jpvt,
                          float[] tau,
                          float[] vn1,
                          float[] vn2,
                          float[] auxv,
                          float[][] f)