Example #1
0
File: lq.go Project: hrautila/gomas
/*
 * Blocked LQ decomposition with compact WY transform. As implemented
 * in lapack.DGELQF subroutine.
 */
func blockedLQ(A, Tvec, Twork, W *cmat.FloatMatrix, lb int, conf *gomas.Config) {
	var ATL, ATR, ABL, ABR, AR cmat.FloatMatrix
	var A00, A11, A12, A21, A22 cmat.FloatMatrix
	var TT, TB cmat.FloatMatrix
	var t0, tau, t2 cmat.FloatMatrix
	var Wrk, w1 cmat.FloatMatrix

	util.Partition2x2(
		&ATL, &ATR,
		&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
	util.Partition2x1(
		&TT,
		&TB, Tvec, 0, util.PTOP)

	//nb := conf.LB
	for m(&ABR)-lb > 0 && n(&ABR)-lb > 0 {
		util.Repartition2x2to3x3(&ATL,
			&A00, nil, nil,
			nil, &A11, &A12,
			nil, &A21, &A22, A, lb, util.PBOTTOMRIGHT)
		util.Repartition2x1to3x1(&TT,
			&t0,
			&tau,
			&t2, Tvec, lb, util.PBOTTOM)

		// current block size
		cb, rb := A11.Size()
		if rb < cb {
			cb = rb
		}
		// --------------------------------------------------------
		// decompose left side AL == /A11\
		//                           \A21/
		w1.SubMatrix(W, 0, 0, cb, 1)
		util.Merge1x2(&AR, &A11, &A12)
		unblockedLQ(&AR, &tau, &w1)

		// build block reflector
		unblkBlockReflectorLQ(Twork, &AR, &tau)

		// update A'tail i.e. A21 and A22 with A'*(I - Y*T*Y.T).T
		// compute: C - Y*(C.T*Y*T).T
		ar, ac := A21.Size()
		Wrk.SubMatrix(W, 0, 0, ar, ac)
		updateRightLQ(&A21, &A22, &A11, &A12, Twork, &Wrk, true, conf)
		// --------------------------------------------------------
		util.Continue3x3to2x2(
			&ATL, &ATR,
			&ABL, &ABR, &A00, &A11, &A22, A, util.PBOTTOMRIGHT)
		util.Continue3x1to2x1(
			&TT,
			&TB, &t0, &tau, Tvec, util.PBOTTOM)
	}

	// last block with unblocked
	if m(&ABR) > 0 && n(&ABR) > 0 {
		w1.SubMatrix(W, 0, 0, m(&ABR), 1)
		unblockedLQ(&ABR, &t2, &w1)
	}
}
Example #2
0
File: rq.go Project: hrautila/gomas
/*
 * Blocked RQ decomposition with compact WY transform. As implemented
 * in lapack.DGERQF subroutine.
 */
func blockedRQ(A, Tvec, Twork, W *cmat.FloatMatrix, lb int, conf *gomas.Config) {
	var ATL, ABR, AL cmat.FloatMatrix
	var A00, A01, A10, A11, A22 cmat.FloatMatrix
	var TT, TB cmat.FloatMatrix
	var t0, tau, t2 cmat.FloatMatrix
	var Wrk, w1 cmat.FloatMatrix

	util.Partition2x2(
		&ATL, nil,
		nil, &ABR /**/, A, 0, 0, util.PBOTTOMRIGHT)
	util.Partition2x1(
		&TT,
		&TB /**/, Tvec, 0, util.PBOTTOM)

	for m(&ATL)-lb > 0 && n(&ATL)-lb > 0 {
		util.Repartition2x2to3x3(&ATL,
			&A00, &A01, nil,
			&A10, &A11, nil,
			nil, nil, &A22 /**/, A, lb, util.PTOPLEFT)
		util.Repartition2x1to3x1(&TT,
			&t0,
			&tau,
			&t2 /**/, Tvec, n(&A11), util.PTOP)

		// current block size
		cb, rb := A11.Size()
		if rb < cb {
			cb = rb
		}
		// --------------------------------------------------------
		// decompose left side AL == ( A10 A11 )
		w1.SubMatrix(W, 0, 0, cb, 1)
		util.Merge1x2(&AL, &A10, &A11)
		unblockedRQ(&AL, &tau, &w1)

		// build block reflector
		unblkBlockReflectorRQ(Twork, &AL, &tau)

		// compute: (A00 A01)(I - Y*T*Y.T)
		ar, ac := A01.Size()
		Wrk.SubMatrix(W, 0, 0, ar, ac)
		updateRightRQ(&A01, &A00, &A11, &A10, Twork, &Wrk, false, conf)
		// --------------------------------------------------------
		util.Continue3x3to2x2(
			&ATL, nil,
			nil, &ABR, &A00, &A11, &A22, A, util.PTOPLEFT)
		util.Continue3x1to2x1(
			&TT,
			&TB, &t0, &tau, Tvec, util.PTOP)
	}

	// last block with unblocked
	if m(&ATL) > 0 && n(&ATL) > 0 {
		w1.SubMatrix(W, 0, 0, m(&ATL), 1)
		unblockedRQ(&ATL, &TT, &w1)
	}
}
Example #3
0
func blkBuildLQ(A, Tvec, Twork, W *cmat.FloatMatrix, K, lb int, conf *gomas.Config) {
	var ATL, ATR, ABL, ABR, AL cmat.FloatMatrix
	var A00, A10, A11, A12, A21, A22 cmat.FloatMatrix
	var tT, tB cmat.FloatMatrix
	var t0, tau, t2, Wrk, D, T cmat.FloatMatrix

	nk := n(A) - K
	mk := m(A) - K
	uk := K % lb
	util.Partition2x2(
		&ATL, &ATR,
		&ABL, &ABR, A, mk+uk, nk+uk, util.PBOTTOMRIGHT)
	util.Partition2x1(
		&tT,
		&tB, Tvec, mk+uk, util.PBOTTOM)

	// zero the bottom part __CHECK HERE: nk? or mk?
	if nk+uk > 0 {
		blasd.Scale(&ABL, 0.0)
		if uk > 0 {
			// number of reflectors is not multiple of blocking factor
			// do the first part with unblocked code.
			unblkBuildLQ(&ABR, &tB, W, m(&ABR)-uk, n(&ABR)-uk, true)
		} else {
			// blocking factor is multiple of K
			blasd.Scale(&ABR, 0.0)
			D.Diag(&ABR)
			blasd.Add(&D, 1.0)
		}
	}

	for m(&ATL) > 0 && n(&ATL) > 0 {
		util.Repartition2x2to3x3(&ATL,
			&A00, nil, nil,
			&A10, &A11, &A12,
			nil, &A21, &A22, A, lb, util.PTOPLEFT)
		util.Repartition2x1to3x1(&tT,
			&t0,
			&tau,
			&t2, Tvec, lb, util.PTOP)
		// ------------------------------------------------------
		util.Merge1x2(&AL, &A11, &A12)

		// build block reflector
		T.SubMatrix(Twork, 0, 0, n(&A11), n(&A11))
		unblkBlockReflectorLQ(&T, &AL, &tau)

		// update A21 and A22 with (I - Y*T*Y.T) from right
		ar, ac := A21.Size()
		Wrk.SubMatrix(W, 0, 0, ar, ac)
		updateRightLQ(&A21, &A22, &A11, &A12, &T, &Wrk, false, conf)

		// update current block
		unblkBuildLQ(&AL, &tau, W, 0, n(&A12), false)

		// zero top rows
		blasd.Scale(&A10, 0.0)
		// ------------------------------------------------------
		util.Continue3x3to2x2(
			&ATL, &ATR,
			&ABL, &ABR, &A00, &A11, &A22, A, util.PTOPLEFT)
		util.Continue3x1to2x1(
			&tT,
			&tB, &t0, &tau, Tvec, util.PTOP)
	}
}
Example #4
0
/*
 * Blocked version for computing C = C*Q and C = C*Q.T from elementary
 * reflectors and scalar coefficients.
 *
 * Elementary reflectors and scalar coefficients are used to build block
 * reflector T. Matrix C is updated by applying block reflector T using
 * compact WY algorithm.
 */
func blockedMultRQRight(C, A, tau, W *cmat.FloatMatrix, flags, lb int, conf *gomas.Config) {
	var ATL, ABR, AL cmat.FloatMatrix
	var A00, A10, A11, A22 cmat.FloatMatrix
	var CL, CR, C0, C1, C2 cmat.FloatMatrix
	var tT, tB cmat.FloatMatrix
	var t0, tau1, t2 cmat.FloatMatrix
	var W0, Wrk, Tw, Twork cmat.FloatMatrix

	var Aref *cmat.FloatMatrix
	var pAdir, pAstart, pDir, pStart, pCstart, pCdir util.Direction
	var bsz, cb, mb, nb, tb int
	var transpose bool

	// partitioning start and direction
	if flags&gomas.TRANS != 0 {
		// from bottom-right to top-left to produce transpose sequence (C*Q.T)
		pAstart = util.PBOTTOMRIGHT
		pAdir = util.PTOPLEFT
		pStart = util.PBOTTOM
		pDir = util.PTOP
		pCstart = util.PRIGHT
		pCdir = util.PLEFT
		mb = 0
		nb = 0
		cb = 0
		tb = 0
		Aref = &ATL
		transpose = false
	} else {
		// from top-left to bottom-right to produce normal sequence (C*Q)
		pAstart = util.PTOPLEFT
		pAdir = util.PBOTTOMRIGHT
		pStart = util.PTOP
		pDir = util.PBOTTOM
		pCstart = util.PLEFT
		pCdir = util.PRIGHT
		mb = imax(0, m(A)-n(A))
		nb = imax(0, n(A)-m(A))
		cb = imax(0, n(C)-m(A))
		tb = imax(0, tau.Len()-m(A))
		Aref = &ABR
		transpose = true
	}

	// intermediate reflector at start of workspace
	Twork.SetBuf(lb, lb, lb, W.Data())
	W0.SetBuf(m(C), lb, m(C), W.Data()[Twork.Len():])

	util.Partition2x2(
		&ATL, nil,
		nil, &ABR /**/, A, mb, nb, pAstart)
	util.Partition1x2(
		&CL, &CR /**/, C, cb, pCstart)
	util.Partition2x1(
		&tT,
		&tB /**/, tau, tb, pStart)

	for m(Aref) > 0 && n(Aref) > 0 {
		util.Repartition2x2to3x3(&ATL,
			&A00, nil, nil,
			&A10, &A11, nil,
			nil, nil, &A22 /**/, A, lb, pAdir)
		bsz = m(&A11) // C1 block size must match A11
		util.Repartition2x1to3x1(&tT,
			&t0,
			&tau1,
			&t2 /**/, tau, bsz, pDir)
		util.Repartition1x2to1x3(&CL,
			&C0, &C1, &C2 /**/, C, bsz, pCdir)
		// --------------------------------------------------------
		// clear & build block reflector from current block
		util.Merge1x2(&AL, &A10, &A11)
		Tw.SubMatrix(&Twork, 0, 0, bsz, bsz)
		blasd.Scale(&Tw, 0.0)
		unblkBlockReflectorRQ(&Tw, &AL, &tau1)

		Wrk.SubMatrix(&W0, 0, 0, m(&C1), bsz)
		updateRightRQ(&C1, &C0, &A11, &A10, &Tw, &Wrk, transpose, conf)
		// --------------------------------------------------------
		util.Continue3x3to2x2(
			&ATL, nil,
			nil, &ABR /**/, &A00, &A11, &A22, A, pAdir)
		util.Continue1x3to1x2(
			&CL, &CR /**/, &C0, &C1, C, pCdir)
		util.Continue3x1to2x1(
			&tT,
			&tB /**/, &t0, &tau1, tau, pDir)
	}

}
Example #5
0
/*
 * Blocked version for computing C = Q*C and C = Q.T*C from elementary
 * reflectors and scalar coefficients.
 *
 * Elementary reflectors and scalar coefficients are used to build block
 * reflector T. Matrix C is updated by applying block reflector T using
 * compact WY algorithm.
 */
func blockedMultLQLeft(C, A, tau, W *cmat.FloatMatrix, flags, lb int, conf *gomas.Config) {
	var ATL, ATR, ABL, ABR, AR cmat.FloatMatrix
	var A00, A11, A12, A22 cmat.FloatMatrix
	var CT, CB, C0, C1, C2 cmat.FloatMatrix
	var tT, tB cmat.FloatMatrix
	var t0, tau1, t2 cmat.FloatMatrix
	var Wrk, W0, Tw, Twork cmat.FloatMatrix

	var Aref *cmat.FloatMatrix
	var pAdir, pAstart, pDir, pStart util.Direction
	var bsz, mb, nb, cb, tb int

	// partitioning start and direction
	if flags&gomas.TRANS != 0 || lb == n(A) {
		// from bottom-right to top-left to produce transposed sequence (Q.T*C)
		pAstart = util.PBOTTOMRIGHT
		pAdir = util.PTOPLEFT
		pStart = util.PBOTTOM
		pDir = util.PTOP
		mb = imax(0, m(A)-n(A))
		nb = imax(0, n(A)-m(A))
		cb = imax(0, m(C)-m(A))
		tb = imax(0, tau.Len()-m(A))
		Aref = &ATL
	} else {
		// from top-left to bottom-right to produce normal sequence (Q*C)
		pAstart = util.PTOPLEFT
		pAdir = util.PBOTTOMRIGHT
		pStart = util.PTOP
		pDir = util.PBOTTOM
		mb = 0
		nb = 0
		cb = 0
		tb = 0
		Aref = &ABR
	}

	util.Partition2x2(
		&ATL, &ATR,
		&ABL, &ABR, A, mb, nb, pAstart)
	util.Partition2x1(
		&CT,
		&CB, C, cb, pStart)
	util.Partition2x1(
		&tT,
		&tB, tau, tb, pStart)

	transpose := flags&gomas.TRANS == 0

	// intermediate reflector at start of workspace
	Twork.SetBuf(lb, lb, lb, W.Data())
	W0.SetBuf(n(C), lb, n(C), W.Data()[Twork.Len():])

	for m(Aref) > 0 && n(Aref) > 0 {
		util.Repartition2x2to3x3(&ATL,
			&A00, nil, nil,
			nil, &A11, &A12,
			nil, nil, &A22, A, lb, pAdir)
		bsz = m(&A11)
		util.Repartition2x1to3x1(&tT,
			&t0,
			&tau1,
			&t2, tau, bsz, pDir)
		util.Repartition2x1to3x1(&CT,
			&C0,
			&C1,
			&C2, C, bsz, pDir)
		// --------------------------------------------------------
		// clear & build block reflector from current block
		util.Merge1x2(&AR, &A11, &A12)
		Tw.SubMatrix(&Twork, 0, 0, bsz, bsz)
		blasd.Scale(&Tw, 0.0)
		unblkBlockReflectorLQ(&Tw, &AR, &tau1)

		// compute: Q*T.C == C - Y*(C.T*Y*T).T  transpose == true
		//          Q*C   == C - C*Y*T*Y.T      transpose == false
		Wrk.SubMatrix(&W0, 0, 0, n(C), bsz)
		updateLeftLQ(&C1, &C2, &A11, &A12, &Tw, &Wrk, transpose, conf)
		// --------------------------------------------------------
		util.Continue3x3to2x2(
			&ATL, &ATR,
			&ABL, &ABR, &A00, &A11, &A22, A, pAdir)
		util.Continue3x1to2x1(
			&CT,
			&CB, &C0, &C1, C, pDir)
		util.Continue3x1to2x1(
			&tT,
			&tB, &t0, &tau1, tau, pDir)
	}

}