org.netlib.lapack
Class Sgeqpf
java.lang.Object
org.netlib.lapack.Sgeqpf
public class Sgeqpf
- 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
* =======
*
* This routine is deprecated and has been replaced by routine SGEQP3.
*
* SGEQPF computes a QR factorization with column pivoting of a
* real M-by-N matrix A: A*P = Q*R.
*
* 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
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the M-by-N matrix A.
* On exit, the upper triangle of the array contains the
* min(M,N)-by-N upper triangular matrix R; the elements
* below the diagonal, together with the array TAU,
* represent the orthogonal matrix Q as a product of
* min(m,n) elementary reflectors.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,M).
*
* JPVT (input/output) INTEGER array, dimension (N)
* On entry, if JPVT(i) .ne. 0, the i-th column of A is permuted
* to the front of A*P (a leading column); if JPVT(i) = 0,
* the i-th column of A is a free column.
* On exit, if JPVT(i) = k, then the i-th column of A*P
* was the k-th column of A.
*
* TAU (output) REAL array, dimension (min(M,N))
* The scalar factors of the elementary reflectors.
*
* WORK (workspace) REAL array, dimension (3*N)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* Further Details
* ===============
*
* The matrix Q is represented as a product of elementary reflectors
*
* Q = H(1) H(2) . . . H(n)
*
* Each H(i) has the form
*
* H = I - tau * v * v'
*
* where tau is a real scalar, and v is a real vector with
* v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i).
*
* The matrix P is represented in jpvt as follows: If
* jpvt(j) = i
* then the jth column of P is the ith canonical unit vector.
*
* Partial column norm updating strategy modified by
* Z. Drmac and Z. Bujanovic, Dept. of Mathematics,
* University of Zagreb, Croatia.
* June 2006.
* For more details see LAPACK Working Note 176.
*
* =====================================================================
*
* .. Parameters ..
Method Summary |
static void |
sgeqpf(int m,
int n,
float[] a,
int _a_offset,
int lda,
int[] jpvt,
int _jpvt_offset,
float[] tau,
int _tau_offset,
float[] work,
int _work_offset,
intW info)
|
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Sgeqpf
public Sgeqpf()
sgeqpf
public static void sgeqpf(int m,
int n,
float[] a,
int _a_offset,
int lda,
int[] jpvt,
int _jpvt_offset,
float[] tau,
int _tau_offset,
float[] work,
int _work_offset,
intW info)