/*
* like LAPACK/dlafrt.f
*
* Build block reflector T from HH reflector stored in TriLU(A) and coefficients
* in tau.
*
* Q = I - Y*T*Y.T; Householder H = I - tau*v*v.T
*
* T = | T 0 | z = -tau*T*Y.T*v
* | z c | c = tau
*
* Q = H(1)H(2)...H(k) building forward here.
*/
func unblkBlockReflectorRQ(T, A, tau *cmat.FloatMatrix) {
var ATL, ABR cmat.FloatMatrix
var A00, a10, A20, a11, a21, A22 cmat.FloatMatrix
var TTL, TBR cmat.FloatMatrix
var T00, t11, t21, T22 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2 cmat.FloatMatrix
util.Partition2x2(
&ATL, nil,
nil, &ABR /**/, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x2(
&TTL, nil,
nil, &TBR /**/, T, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&tT,
&tB /**/, tau, 0, util.PBOTTOM)
for m(&ATL) > 0 && n(&ATL) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&a10, &a11, nil,
&A20, &a21, &A22 /**/, A, 1, util.PTOPLEFT)
util.Repartition2x2to3x3(&TTL,
&T00, nil, nil,
nil, &t11, nil,
nil, &t21, &T22 /**/, T, 1, util.PTOPLEFT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2 /**/, tau, 1, util.PTOP)
// --------------------------------------------------
// t11 := tau
tauval := tau1.Get(0, 0)
if tauval != 0.0 {
t11.Set(0, 0, tauval)
// t21 := -tauval*(a21 + A20*a10)
blasd.Axpby(&t21, &a21, 1.0, 0.0)
blasd.MVMult(&t21, &A20, &a10, -tauval, -tauval, gomas.NONE)
// t21 := T22*t21
blasd.MVMultTrm(&t21, &T22, 1.0, gomas.LOWER)
}
// --------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR /**/, &A00, &a11, &A22, A, util.PTOPLEFT)
util.Continue3x3to2x2(
&TTL, nil,
nil, &TBR /**/, &T00, &t11, &T22, T, util.PTOPLEFT)
util.Continue3x1to2x1(
&tT,
&tB /**/, &t0, &tau1, tau, util.PTOP)
}
}
/*
* like LAPACK/dlafrt.f
*
* Build block reflector T from HH reflector stored in TriLU(A) and coefficients
* in tau.
*
* Q = I - Y*T*Y.T; Householder H = I - tau*v*v.T
*
* T = | T z | z = -tau*T*Y.T*v
* | 0 c | c = tau
*
* Q = H(1)H(2)...H(k) building forward here.
*/
func unblkQLBlockReflector(T, A, tau *cmat.FloatMatrix) {
var ATL, ABR cmat.FloatMatrix
var A00, a01, a11, A02, a12, A22 cmat.FloatMatrix
var TTL, TBR cmat.FloatMatrix
var T00, t11, t21, T22 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2 cmat.FloatMatrix
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x2(
&TTL, nil,
nil, &TBR, T, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&tT,
&tB, tau, 0, util.PBOTTOM)
for m(&ATL) > 0 && n(&ATL) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, &A02,
nil, &a11, &a12,
nil, nil, &A22, A, 1, util.PTOPLEFT)
util.Repartition2x2to3x3(&TTL,
&T00, nil, nil,
nil, &t11, nil,
nil, &t21, &T22, T, 1, util.PTOPLEFT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, tau, 1, util.PTOP)
// --------------------------------------------------
// t11 := tau
tauval := tau1.Get(0, 0)
if tauval != 0.0 {
t11.Set(0, 0, tauval)
// t21 := -tauval*(a12.T + &A02.T*a12)
blasd.Axpby(&t21, &a12, 1.0, 0.0)
blasd.MVMult(&t21, &A02, &a01, -tauval, -tauval, gomas.TRANSA)
// t21 := T22*t01
blasd.MVMultTrm(&t21, &T22, 1.0, gomas.LOWER)
}
// --------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &a11, &A22, A, util.PTOPLEFT)
util.Continue3x3to2x2(
&TTL, nil,
nil, &TBR, &T00, &t11, &T22, T, util.PTOPLEFT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, tau, util.PTOP)
}
}
/*
* like LAPACK/dlafrt.f
*
* Build block reflector T from HH reflector stored in TriLU(A) and coefficients
* in tau.
*
* Q = I - Y*T*Y.T; Householder H = I - tau*v*v.T
*
* T = | T z | z = -tau*T*Y.T*v
* | 0 c | c = tau
*
* Q = H(1)H(2)...H(k) building forward here.
*/
func unblkBlockReflectorLQ(T, A, tau *cmat.FloatMatrix) {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a01, A02, a11, a12, A22 cmat.FloatMatrix
var TTL, TTR, TBL, TBR cmat.FloatMatrix
var T00, t01, T02, t11, t12, T22 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition2x2(
&TTL, &TTR,
&TBL, &TBR, T, 0, 0, util.PTOPLEFT)
util.Partition2x1(
&tT,
&tB, tau, 0, util.PTOP)
for m(&ABR) > 0 && n(&ABR) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, &A02,
nil, &a11, &a12,
nil, nil, &A22, A, 1, util.PBOTTOMRIGHT)
util.Repartition2x2to3x3(&TTL,
&T00, &t01, &T02,
nil, &t11, &t12,
nil, nil, &T22, T, 1, util.PBOTTOMRIGHT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, tau, 1, util.PBOTTOM)
// --------------------------------------------------
// t11 := tau
tauval := tau1.Get(0, 0)
if tauval != 0.0 {
t11.Set(0, 0, tauval)
// t01 := -tauval*(a01 + A02*a12)
blasd.Axpby(&t01, &a01, 1.0, 0.0)
blasd.MVMult(&t01, &A02, &a12, -tauval, -tauval, gomas.NONE)
// t01 := T00*t01
blasd.MVMultTrm(&t01, &T00, 1.0, gomas.UPPER)
}
// --------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x3to2x2(
&TTL, &TTR,
&TBL, &TBR, &T00, &t11, &T22, T, util.PBOTTOMRIGHT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, tau, util.PBOTTOM)
}
}
/*
* Unblocked QR decomposition with block reflector T.
*/
func unblockedQRT(A, T, W *cmat.FloatMatrix) *gomas.Error {
var err *gomas.Error = nil
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a10, a11, a12, A20, a21, A22 cmat.FloatMatrix
var TTL, TTR, TBL, TBR cmat.FloatMatrix
var T00, t01, T02, t11, t12, T22, w12 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition2x2(
&TTL, &TTR,
&TBL, &TBR, T, 0, 0, util.PTOPLEFT)
for m(&ABR) > 0 && n(&ABR) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&a10, &a11, &a12,
&A20, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
util.Repartition2x2to3x3(&TTL,
&T00, &t01, &T02,
nil, &t11, &t12,
nil, nil, &T22, T, 1, util.PBOTTOMRIGHT)
// ------------------------------------------------------
computeHouseholder(&a11, &a21, &t11)
// H*[a12 A22].T
w12.SubMatrix(W, 0, 0, a12.Len(), 1)
applyHouseholder2x1(&t11, &a21, &a12, &A22, &w12, gomas.LEFT)
// update T
tauval := t11.Get(0, 0)
if tauval != 0.0 {
// t01 := -tauval*(a10.T + &A20.T*a21)
//a10.CopyTo(&t01)
blasd.Axpby(&t01, &a10, 1.0, 0.0)
blasd.MVMult(&t01, &A20, &a21, -tauval, -tauval, gomas.TRANSA)
// t01 := T00*t01
blasd.MVMultTrm(&t01, &T00, 1.0, gomas.UPPER)
}
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x3to2x2(
&TTL, &TTR,
&TBL, &TBR, &T00, &t11, &T22, T, util.PBOTTOMRIGHT)
}
return err
}
/*
* Build full block reflect T for nc columns from sequence of reflector stored in S.
* Reflectors in S are the diagonal of T, off-diagonal values of reflector are computed
* from elementary reflector store in lower triangular part of A.
*/
func buildQRTReflector(T, A, S *cmat.FloatMatrix, nc int, conf *gomas.Config) *gomas.Error {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, A10, A11, A20, A21, A22 cmat.FloatMatrix
var TTL, TTR, TBL, TBR cmat.FloatMatrix
var T00, T01, T02, T11, T12, T22 cmat.FloatMatrix
var SL, SR cmat.FloatMatrix
var S00, S01, S02 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition2x2(
&TTL, &TTR,
&TBL, &TBR, T, 0, 0, util.PTOPLEFT)
util.Partition1x2(
&SL, &SR, S, 0, util.PLEFT)
nb := conf.LB
for m(&ABR)-nb > 0 && n(&ABR)-nb > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&A10, &A11, nil,
&A20, &A21, &A22, A, nb, util.PBOTTOMRIGHT)
util.Repartition2x2to3x3(&TTL,
&T00, &T01, &T02,
nil, &T11, &T12,
nil, nil, &T22, T, nb, util.PBOTTOMRIGHT)
util.Repartition1x2to1x3(&SL,
&S00, &S01, &S02, S, nb, util.PRIGHT)
// --------------------------------------------------------
// update T01: T01 = -T00*Y1.T*Y2*T11
// Y1 = /A10\ Y2 = /A11\
// \A20/ \A21/
//
T11.Copy(&S01)
updateQRTReflector(&T01, &A10, &A20, &A11, &A21, &T00, &S01, conf)
// --------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &A11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x3to2x2(
&TTL, &TTR,
&TBL, &TBR, &T00, &T11, &T22, T, util.PBOTTOMRIGHT)
util.Continue1x3to1x2(
&SL, &SR, &S00, &S01, S, util.PRIGHT)
}
if m(&ABR) > 0 && n(&ABR) > 0 {
}
return nil
}
/*
* 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)
}
}
// blocked LU decomposition w/o pivots, FLAME LU nopivots variant 5
func blockedLUnoPiv(A *cmat.FloatMatrix, nb int, conf *gomas.Config) *gomas.Error {
var err *gomas.Error = nil
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, A01, A02, A10, A11, A12, A20, A21, A22 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
for m(&ATL) < m(A)-nb {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, &A02,
&A10, &A11, &A12,
&A20, &A21, &A22, A, nb, util.PBOTTOMRIGHT)
// A00 = LU(A00)
unblockedLUnoPiv(&A11, conf)
// A12 = trilu(A00)*A12.-1 (TRSM)
blasd.SolveTrm(&A12, &A11, 1.0, gomas.LEFT|gomas.LOWER|gomas.UNIT)
// A21 = A21.-1*triu(A00) (TRSM)
blasd.SolveTrm(&A21, &A11, 1.0, gomas.RIGHT|gomas.UPPER)
// A22 = A22 - A21*A12
blasd.Mult(&A22, &A21, &A12, -1.0, 1.0, gomas.NONE)
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &A11, &A22, A, util.PBOTTOMRIGHT)
}
// last block
if m(&ATL) < m(A) {
unblockedLUnoPiv(&ABR, conf)
}
return err
}
/*
* Blocked QR decomposition with compact WY transform.
*
* Compatible with lapack.DGEQRF.
*/
func blockedQL(A, Tvec, Twork, W *cmat.FloatMatrix, lb int, conf *gomas.Config) {
var ATL, ATR, ABL, 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, &ATR,
&ABL, &ABR, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&TT,
&TB, Tvec, 0, util.PBOTTOM)
nb := lb
for m(&ATL)-nb > 0 && n(&ATL)-nb > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, nil,
&A10, &A11, nil,
nil, nil, &A22, A, nb, util.PTOPLEFT)
util.Repartition2x1to3x1(&TT,
&t0,
&tau,
&t2, Tvec, nb, util.PTOP)
// current block size
cb, rb := A11.Size()
if rb < cb {
cb = rb
}
// --------------------------------------------------------
// decompose righ side AL == /A01\
// \A11/
w1.SubMatrix(W, 0, 0, cb, 1)
util.Merge2x1(&AL, &A01, &A11)
unblockedQL(&AL, &tau, &w1)
// build block reflector
unblkQLBlockReflector(Twork, &AL, &tau)
// update A'tail i.e. A10 and A00 with (I - Y*T*Y.T).T * A'tail
// compute: C - Y*(C.T*Y*T).T
ar, ac := A10.Size()
Wrk.SubMatrix(W, 0, 0, ac, ar)
updateQLLeft(&A10, &A00, &A11, &A01, Twork, &Wrk, true, conf)
// --------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &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, n(&ATL), 1)
unblockedQL(&ATL, &t0, &w1)
}
}
// unblocked LU decomposition w/o pivots, FLAME LU nopivots variant 5
func unblockedLUnoPiv(A *cmat.FloatMatrix, conf *gomas.Config) *gomas.Error {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a01, A02, a10, a11, a12, A20, a21, A22 cmat.FloatMatrix
var err *gomas.Error = nil
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
for m(&ATL) < m(A) {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, &A02,
&a10, &a11, &a12,
&A20, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
// a21 = a21/a11
blasd.InvScale(&a21, a11.Get(0, 0))
// A22 = A22 - a21*a12
blasd.MVUpdate(&A22, &a21, &a12, -1.0)
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
}
return err
}
/*
* Reduce upper triangular matrix to tridiagonal.
*
* Elementary reflectors Q = H(n-1)...H(2)H(1) are stored on upper
* triangular part of A. Reflector H(n-1) saved at column A(n) and
* scalar multiplier to tau[n-1]. If parameter `tail` is true then
* this function is used to reduce tail part of partially reduced
* matrix and tau-vector partitioning is starting from last position.
*/
func unblkReduceTridiagUpper(A, tauq, W *cmat.FloatMatrix, tail bool) {
var ATL, ABR cmat.FloatMatrix
var A00, a01, a11, A22 cmat.FloatMatrix
var tqT, tqB, tq0, tauq1, tq2 cmat.FloatMatrix
var y21 cmat.FloatMatrix
var v0 float64
toff := 1
if tail {
toff = 0
}
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&tqT,
&tqB, tauq, toff, util.PBOTTOM)
for n(&ATL) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, nil,
nil, &a11, nil,
nil, nil, &A22, A, 1, util.PTOPLEFT)
util.Repartition2x1to3x1(&tqT,
&tq0,
&tauq1,
&tq2, tauq, 1, util.PTOP)
// set temp vectors for this round
y21.SetBuf(n(&A00), 1, n(&A00), W.Data())
// ------------------------------------------------------
// Compute householder to zero super-diagonal entries
computeHouseholderRev(&a01, &tauq1)
tauqv := tauq1.Get(0, 0)
// set superdiagonal to unit
v0 = a01.Get(-1, 0)
a01.Set(-1, 0, 1.0)
// y21 := A22*a12t
blasd.MVMultSym(&y21, &A00, &a01, tauqv, 0.0, gomas.UPPER)
// beta := tauq*a12t*y21
beta := tauqv * blasd.Dot(&a01, &y21)
// y21 := y21 - 0.5*beta*a125
blasd.Axpy(&y21, &a01, -0.5*beta)
// A22 := A22 - a12t*y21.T - y21*a12.T
blasd.MVUpdate2Sym(&A00, &a01, &y21, -1.0, gomas.UPPER)
// restore superdiagonal value
a01.Set(-1, 0, v0)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &a11, &A22, A, util.PTOPLEFT)
util.Continue3x1to2x1(
&tqT,
&tqB, &tq0, &tauq1, tauq, util.PTOP)
}
}
func blkReduceTridiagUpper(A, tauq, Y, W *cmat.FloatMatrix, lb int, conf *gomas.Config) {
var ATL, ABR cmat.FloatMatrix
var A00, A01, A11, A22 cmat.FloatMatrix
var YT, YB, Y0, Y1, Y2 cmat.FloatMatrix
var tqT, tqB, tq0, tauq1, tq2 cmat.FloatMatrix
var v0 float64
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&YT,
&YB, Y, 0, util.PBOTTOM)
util.Partition2x1(
&tqT,
&tqB, tauq, 1, util.PBOTTOM)
for m(&ATL)-lb > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, nil,
nil, &A11, nil,
nil, nil, &A22, A, lb, util.PTOPLEFT)
util.Repartition2x1to3x1(&YT,
&Y0,
&Y1,
&Y2, Y, lb, util.PTOP)
util.Repartition2x1to3x1(&tqT,
&tq0,
&tauq1,
&tq2, tauq, lb, util.PTOP)
// ------------------------------------------------------
unblkBuildTridiagUpper(&ATL, &tauq1, &YT, W)
// set subdiagonal entry to unit
v0 = A01.Get(-1, 0)
A01.Set(-1, 0, 1.0)
// A22 := A22 - A01*Y0.T - Y0*A01.T
blasd.Update2Sym(&A00, &A01, &Y0, -1.0, 1.0, gomas.UPPER, conf)
// restore subdiagonal entry
A01.Set(-1, 0, v0)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &A11, &A22, A, util.PTOPLEFT)
util.Continue3x1to2x1(
&YT,
&YB, &Y0, &Y1, Y, util.PTOP)
util.Continue3x1to2x1(
&tqT,
&tqB, &tq0, &tauq1, tauq, util.PTOP)
}
if m(&ATL) > 0 {
unblkReduceTridiagUpper(&ATL, &tqT, W, true)
}
}
/*
* 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)
}
}
/*
* Tridiagonal reduction of LOWER triangular symmetric matrix, zero elements below 1st
* subdiagonal:
*
* A = (1 - tau*u*u.t)*A*(1 - tau*u*u.T)
* = (I - tau*( 0 0 )) (a11 a12) (I - tau*( 0 0 ))
* ( ( 0 u*u.t)) (a21 A22) ( ( 0 u*u.t))
*
* a11, a12, a21 not affected
*
* from LEFT:
* A22 = A22 - tau*u*u.T*A22
* from RIGHT:
* A22 = A22 - tau*A22*u.u.T
*
* LEFT and RIGHT:
* A22 = A22 - tau*u*u.T*A22 - tau*(A22 - tau*u*u.T*A22)*u*u.T
* = A22 - tau*u*u.T*A22 - tau*A22*u*u.T + tau*tau*u*u.T*A22*u*u.T
* [x = tau*A22*u (vector)] (SYMV)
* A22 = A22 - u*x.T - x*u.T + tau*u*u.T*x*u.T
* [beta = tau*u.T*x (scalar)] (DOT)
* = A22 - u*x.T - x*u.T + beta*u*u.T
* = A22 - u*(x - 0.5*beta*u).T - (x - 0.5*beta*u)*u.T
* [w = x - 0.5*beta*u] (AXPY)
* = A22 - u*w.T - w*u.T (SYR2)
*
* Result of reduction for N = 5:
* ( d . . . . )
* ( e d . . . )
* ( v1 e d . . )
* ( v1 v2 e d . )
* ( v1 v2 v3 e d )
*/
func unblkReduceTridiagLower(A, tauq, W *cmat.FloatMatrix) {
var ATL, ABR cmat.FloatMatrix
var A00, a11, a21, A22 cmat.FloatMatrix
var tqT, tqB, tq0, tauq1, tq2 cmat.FloatMatrix
var y21 cmat.FloatMatrix
var v0 float64
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition2x1(
&tqT,
&tqB, tauq, 0, util.PTOP)
for m(&ABR) > 0 && n(&ABR) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
nil, &a11, nil,
nil, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
util.Repartition2x1to3x1(&tqT,
&tq0,
&tauq1,
&tq2, tauq, 1, util.PBOTTOM)
// set temp vectors for this round
y21.SetBuf(n(&A22), 1, n(&A22), W.Data())
// ------------------------------------------------------
// Compute householder to zero subdiagonal entries
computeHouseholderVec(&a21, &tauq1)
tauqv := tauq1.Get(0, 0)
// set subdiagonal to unit
v0 = a21.Get(0, 0)
a21.Set(0, 0, 1.0)
// y21 := tauq*A22*a21
blasd.MVMultSym(&y21, &A22, &a21, tauqv, 0.0, gomas.LOWER)
// beta := tauq*a21.T*y21
beta := tauqv * blasd.Dot(&a21, &y21)
// y21 := y21 - 0.5*beta*a21
blasd.Axpy(&y21, &a21, -0.5*beta)
// A22 := A22 - a21*y21.T - y21*a21.T
blasd.MVUpdate2Sym(&A22, &a21, &y21, -1.0, gomas.LOWER)
// restore subdiagonal
a21.Set(0, 0, v0)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x1to2x1(
&tqT,
&tqB, &tq0, &tauq1, tauq, util.PBOTTOM)
}
}
func blockedCHOL(A *cmat.FloatMatrix, flags int, conf *gomas.Config) *gomas.Error {
var err, firstErr *gomas.Error
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, A01, A02, A10, A11, A12, A20, A21, A22 cmat.FloatMatrix
nb := conf.LB
err = nil
firstErr = nil
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
for m(A)-m(&ATL) > nb {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, &A02,
&A10, &A11, &A12,
&A20, &A21, &A22, A, nb, util.PBOTTOMRIGHT)
if flags&gomas.LOWER != 0 {
// A11 = chol(A11)
err = unblockedLowerCHOL(&A11, flags, m(&ATL))
// A21 = A21 * tril(A11).-1
blasd.SolveTrm(&A21, &A11, 1.0, gomas.RIGHT|gomas.LOWER|gomas.TRANSA, conf)
// A22 = A22 - A21*A21.T
blasd.UpdateSym(&A22, &A21, -1.0, 1.0, gomas.LOWER, conf)
} else {
// A11 = chol(A11)
err = unblockedUpperCHOL(&A11, flags, m(&ATL))
// A12 = triu(A11).-1 * A12
blasd.SolveTrm(&A12, &A11, 1.0, gomas.UPPER|gomas.TRANSA, conf)
// A22 = A22 - A12.T*A12
blasd.UpdateSym(&A22, &A12, -1.0, 1.0, gomas.UPPER|gomas.TRANSA, conf)
}
if err != nil && firstErr == nil {
firstErr = err
}
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &A11, &A22, A, util.PBOTTOMRIGHT)
}
if m(&ATL) < m(A) {
// last block
if flags&gomas.LOWER != 0 {
unblockedLowerCHOL(&ABR, flags, 0)
} else {
unblockedUpperCHOL(&ABR, flags, 0)
}
}
return firstErr
}
/*
* Unblocked code for generating M by N matrix Q with orthogonal columns which
* are defined as the last N columns of the product of K first elementary
* reflectors.
*
* Parameter nk is last nk elementary reflectors that are not used in computing
* the matrix Q. Parameter mk length of the first unused elementary reflectors
* First nk columns are zeroed and subdiagonal mk-nk is set to unit.
*
* Compatible with lapack.DORG2L subroutine.
*/
func unblkBuildQL(A, Tvec, W *cmat.FloatMatrix, mk, nk int, mayClear bool) {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a01, a10, a11, a21, A22 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2, w12, D cmat.FloatMatrix
// (mk, nk) = (rows, columns) of upper left partition
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, mk, nk, util.PTOPLEFT)
util.Partition2x1(
&tT,
&tB, Tvec, nk, util.PTOP)
// zero the left side
if nk > 0 && mayClear {
blasd.Scale(&ABL, 0.0)
blasd.Scale(&ATL, 0.0)
D.Diag(&ATL, nk-mk)
blasd.Add(&D, 1.0)
}
for m(&ABR) > 0 && n(&ABR) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, nil,
&a10, &a11, nil,
nil, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, Tvec, 1, util.PBOTTOM)
// ------------------------------------------------------
w12.SubMatrix(W, 0, 0, a10.Len(), 1)
applyHouseholder2x1(&tau1, &a01, &a10, &A00, &w12, gomas.LEFT)
blasd.Scale(&a01, -tau1.Get(0, 0))
a11.Set(0, 0, 1.0-tau1.Get(0, 0))
// zero bottom elements
blasd.Scale(&a21, 0.0)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, Tvec, util.PBOTTOM)
}
}
/*
* Unblocked code for generating M by N matrix Q with orthogonal columns which
* are defined as the first N columns of the product of K first elementary
* reflectors.
*
* Parameters nk = n(A)-K, mk = m(A)-K define the initial partitioning of
* matrix A.
*
* Q = H(k)H(k-1)...H(1) , 0 < k <= M, where H(i) = I - tau*v*v.T
*
* Computation is ordered as H(k)*H(k-1)...*H(1)*I ie. from bottom to top.
*
* If k < M rows k+1:M are cleared and diagonal entries [k+1:M,k+1:M] are
* set to unit. Then the matrix Q is generated by right multiplying elements below
* of i'th elementary reflector H(i).
*
* Compatible to lapack.xORG2L subroutine.
*/
func unblkBuildLQ(A, Tvec, W *cmat.FloatMatrix, mk, nk int, mayClear bool) {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a10, a11, a12, a21, A22 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2, w12, D cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, mk, nk, util.PBOTTOMRIGHT)
util.Partition2x1(
&tT,
&tB, Tvec, mk, util.PBOTTOM)
// zero the bottom part
if mk > 0 && mayClear {
blasd.Scale(&ABL, 0.0)
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, 1, util.PTOPLEFT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, Tvec, 1, util.PTOP)
// ------------------------------------------------------
w12.SubMatrix(W, 0, 0, a21.Len(), 1)
applyHouseholder2x1(&tau1, &a12, &a21, &A22, &w12, gomas.RIGHT)
blasd.Scale(&a12, -tau1.Get(0, 0))
a11.Set(0, 0, 1.0-tau1.Get(0, 0))
// zero
blasd.Scale(&a10, 0.0)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PTOPLEFT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, Tvec, util.PTOP)
}
}
func blockedQRT(A, T, W *cmat.FloatMatrix, conf *gomas.Config) *gomas.Error {
var err *gomas.Error = nil
var ATL, ATR, ABL, ABR, AL, AR cmat.FloatMatrix
var A00, A01, A02, A10, A11, A12, A20, A21, A22 cmat.FloatMatrix
var TL, TR, W2 cmat.FloatMatrix
var T00, T01, T02 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition1x2(
&TL, &TR, T, 0, util.PLEFT)
nb := conf.LB
for m(&ABR)-nb > 0 && n(&ABR)-nb > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, &A02,
&A10, &A11, &A12,
&A20, &A21, &A22, A, nb, util.PBOTTOMRIGHT)
util.Repartition1x2to1x3(&TL,
&T00, &T01, &T02, T, nb, util.PRIGHT)
util.Partition1x2(
&AL, &AR, &ABR, nb, util.PLEFT)
// --------------------------------------------------------
// decompose left side AL == /A11\
// \A21/
unblockedQRT(&AL, &T01, W)
// update A'tail i.e. A12 and A22 with (I - Y*T*Y.T).T * A'tail
// compute: Q*T.C == C - Y*(C.T*Y*T).T
ar, ac := A12.Size()
W2.SubMatrix(W, 0, 0, ac, ar)
updateWithQTLeft(&A12, &A22, &A11, &A21, &T01, &W2, true, conf)
// --------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &A11, &A22, A, util.PBOTTOMRIGHT)
util.Continue1x3to1x2(
&TL, &TR, &T00, &T01, T, util.PRIGHT)
}
if m(&ABR) > 0 && n(&ABR) > 0 {
T01.SubMatrix(&TR, 0, 0, n(&ABR), n(&ABR))
unblockedQRT(&ABR, &T01, W)
}
return err
}
func trdsecEigenBuildInplace(Q, z *cmat.FloatMatrix) {
var QTL, QBR, Q00, q11, q12, q21, Q22, qi cmat.FloatMatrix
var zk0, zk1, dk0, dk1 float64
util.Partition2x2(
&QTL, nil,
nil, &QBR /**/, Q, 0, 0, util.PTOPLEFT)
for m(&QBR) > 0 {
util.Repartition2x2to3x3(&QTL,
&Q00, nil, nil,
nil, &q11, &q12,
nil, &q21, &Q22 /**/, Q, 1, util.PBOTTOMRIGHT)
//---------------------------------------------------------------
k := m(&Q00)
zk0 = z.GetAt(k)
dk0 = q11.Get(0, 0)
q11.Set(0, 0, zk0/dk0)
for i := 0; i < q12.Len(); i++ {
zk1 = z.GetAt(k + i + 1)
dk0 = q12.GetAt(i)
dk1 = q21.GetAt(i)
q12.SetAt(i, zk0/dk1)
q21.SetAt(i, zk1/dk0)
}
//---------------------------------------------------------------
util.Continue3x3to2x2(
&QTL, nil,
nil, &QBR /**/, &Q00, &q11, &Q22 /**/, Q, util.PBOTTOMRIGHT)
}
// scale column eigenvectors
for k := 0; k < z.Len(); k++ {
qi.Column(Q, k)
t := blasd.Nrm2(&qi)
blasd.InvScale(&qi, t)
}
}
func unblockedLowerCHOL(A *cmat.FloatMatrix, flags int, nr int) (err *gomas.Error) {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a10, a11, A20, a21, A22 cmat.FloatMatrix
err = nil
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
for m(&ATL) < m(A) {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&a10, &a11, nil,
&A20, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
// a11 = sqrt(a11)
aval := a11.Get(0, 0)
if aval < 0.0 {
if err == nil {
err = gomas.NewError(gomas.ENEGATIVE, "DecomposeCHOL", m(&ATL)+nr)
}
} else {
a11.Set(0, 0, math.Sqrt(aval))
}
// a21 = a21/a11
blasd.InvScale(&a21, a11.Get(0, 0))
// A22 = A22 - a21*a21' (SYR)
blasd.MVUpdateSym(&A22, &a21, -1.0, gomas.LOWER)
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
}
return
}
/*
* Unblocked RQ decomposition. As implemented
* in lapack.DGERQ2 subroutine.
*/
func unblockedRQ(A, Tvec, W *cmat.FloatMatrix) {
var ATL, ABR cmat.FloatMatrix
var A00, a11, a01, a10, A22 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2, w12 cmat.FloatMatrix
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&tT,
&tB, Tvec, 0, util.PBOTTOM)
for m(&ATL) > 0 && n(&ATL) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, nil,
&a10, &a11, nil,
nil, nil, &A22, A, 1, util.PTOPLEFT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, Tvec, 1, util.PTOP)
// ------------------------------------------------------
computeHouseholder(&a11, &a10, &tau1)
w12.SubMatrix(W, 0, 0, a01.Len(), 1)
applyHouseholder2x1(&tau1, &a10, &a01, &A00, &w12, gomas.RIGHT)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &a11, &A22, A, util.PTOPLEFT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, Tvec, util.PTOP)
}
}
/*
* 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 blockedMultQRight(C, A, tau, W *cmat.FloatMatrix, flags, nb int, conf *gomas.Config) {
var ATL, ATR, ABL, ABR, AL cmat.FloatMatrix
var A00, A10, A11, A20, A21, 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 int
// 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 = imax(0, m(A)-n(A))
cb = n(C) - n(A)
Aref = &ATL
} 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 = 0
cb = 0
Aref = &ABR
}
// intermediate reflector at start of workspace
Twork.SetBuf(nb, nb, nb, W.Data())
W0.SetBuf(m(C), nb, m(C), W.Data()[Twork.Len():])
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, mb, 0, pAstart)
util.Partition1x2(
&CL, &CR, C, cb, pCstart)
util.Partition2x1(
&tT,
&tB, tau, 0, pStart)
transpose := flags&gomas.TRANS != 0
for m(Aref) > 0 && n(Aref) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&A10, &A11, nil,
&A20, &A21, &A22, A, nb, pAdir)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, tau, nb, pDir)
bsz = n(&A11) // C1 block size must match A11
util.Repartition1x2to1x3(&CL,
&C0, &C1, &C2, C, bsz, pCdir)
// --------------------------------------------------------
// clear & build block reflector from current block
util.Merge2x1(&AL, &A11, &A21)
Tw.SubMatrix(&Twork, 0, 0, bsz, bsz)
blasd.Scale(&Tw, 0.0)
unblkQRBlockReflector(&Tw, &AL, &tau1)
// compute: C*Q.T == C - C*(Y*T*Y.T).T = C - C*Y*T.T*Y.T
// C*Q == C - C*Y*T*Y.T
Wrk.SubMatrix(&W0, 0, 0, m(&C1), bsz)
updateWithQTRight(&C1, &C2, &A11, &A21, &Tw, &Wrk, transpose, conf)
// --------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &A11, &A22, A, pAdir)
util.Continue1x3to1x2(
&CL, &CR, &C0, &C1, C, pCdir)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, tau, pDir)
}
}
/*
* Computes upper Hessenberg reduction of N-by-N matrix A using unblocked
* algorithm as described in (1).
*
* Hessengerg reduction: A = Q.T*B*Q, Q unitary, B upper Hessenberg
* Q = H(0)*H(1)*...*H(k) where H(k) is k'th Householder reflector.
*
* Compatible with lapack.DGEHD2.
*/
func unblkHessGQvdG(A, Tvec, W *cmat.FloatMatrix, row int) {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a11, a21, A22 cmat.FloatMatrix
var AL, AR, A0, a1, A2 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2, w12, v1 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, row, 0, util.PTOPLEFT)
util.Partition1x2(
&AL, &AR, A, 0, util.PLEFT)
util.Partition2x1(
&tT,
&tB, Tvec, 0, util.PTOP)
v1.SubMatrix(W, 0, 0, m(A), 1)
for m(&ABR) > 1 && n(&ABR) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
nil, &a11, nil,
nil, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
util.Repartition1x2to1x3(&AL,
&A0, &a1, &A2, A, 1, util.PRIGHT)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, Tvec, 1, util.PBOTTOM)
// ------------------------------------------------------
// a21 = [beta; H(k)].T
computeHouseholderVec(&a21, &tau1)
tauval := tau1.Get(0, 0)
beta := a21.Get(0, 0)
a21.Set(0, 0, 1.0)
// v1 := A2*a21
blasd.MVMult(&v1, &A2, &a21, 1.0, 0.0, gomas.NONE)
// A2 := A2 - tau*v1*a21 (A2 := A2*H(k))
blasd.MVUpdate(&A2, &v1, &a21, -tauval)
w12.SubMatrix(W, 0, 0, n(&A22), 1)
// w12 := a21.T*A22 = A22.T*a21
blasd.MVMult(&w12, &A22, &a21, 1.0, 0.0, gomas.TRANS)
// A22 := A22 - tau*a21*w12 (A22 := H(k)*A22)
blasd.MVUpdate(&A22, &a21, &w12, -tauval)
a21.Set(0, 0, beta)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
util.Continue1x3to1x2(
&AL, &AR, &A0, &a1, A, util.PRIGHT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, Tvec, util.PBOTTOM)
}
}
/*
* Blocked version of Hessenberg reduction algorithm as presented in (1). This
* version uses compact-WY transformation.
*
* Some notes:
*
* Elementary reflectors stored in [A11; A21].T are not on diagonal of A11. Update of
* a block aligned with A11; A21 is as follow
*
* 1. Update from left Q(k)*C:
* c0 0 c0
* (I - Y*T*Y.T).T*C = C - Y*(C.T*Y)*T.T = C1 - Y1 * (C1.T.Y1+C2.T*Y2)*T.T = C1-Y1*W
* C2 Y2 C2-Y2*W
*
* where W = (C1.T*Y1+C2.T*Y2)*T.T and first row of C is not affected by update
*
* 2. Update from right C*Q(k):
* 0
* C - C*Y*T*Y.T = c0;C1;C2 - c0;C1;C2 * Y1 *T*(0;Y1;Y2) = c0; C1-W*Y1; C2-W*Y2
* Y2
* where W = (C1*Y1 + C2*Y2)*T and first column of C is not affected
*
*/
func blkHessGQvdG(A, Tvec, W *cmat.FloatMatrix, nb int, conf *gomas.Config) *gomas.Error {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, A11, A12, A21, A22, A2 cmat.FloatMatrix
var tT, tB, td cmat.FloatMatrix
var t0, t1, t2, T cmat.FloatMatrix
var V, VT, VB /*V0, V1, V2,*/, Y1, Y2, W0 cmat.FloatMatrix
//fmt.Printf("blkHessGQvdG...\n")
T.SubMatrix(W, 0, 0, conf.LB, conf.LB)
V.SubMatrix(W, conf.LB, 0, m(A), conf.LB)
td.Diag(&T)
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition2x1(
&tT,
&tB, Tvec, 0, util.PTOP)
for m(&ABR) > nb+1 && n(&ABR) > nb {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
nil, &A11, &A12,
nil, &A21, &A22, A, nb, util.PBOTTOMRIGHT)
util.Repartition2x1to3x1(&tT,
&t0,
&t1,
&t2, Tvec, nb, util.PBOTTOM)
util.Partition2x1(
&VT,
&VB, &V, m(&ATL), util.PTOP)
// ------------------------------------------------------
unblkBuildHessGQvdG(&ABR, &T, &VB, nil)
blasd.Copy(&t1, &td)
// m(Y) == m(ABR)-1, n(Y) == n(A11)
Y1.SubMatrix(&ABR, 1, 0, n(&A11), n(&A11))
Y2.SubMatrix(&ABR, 1+n(&A11), 0, m(&A21)-1, n(&A11))
// [A01; A02] == ATR := ATR*(I - Y*T*Y.T)
updateHessRightWY(&ATR, &Y1, &Y2, &T, &VT, conf)
// A2 = [A12; A22].T
util.Merge2x1(&A2, &A12, &A22)
// A2 := A2 - VB*T*A21.T
be := A21.Get(0, -1)
A21.Set(0, -1, 1.0)
blasd.MultTrm(&VB, &T, 1.0, gomas.UPPER|gomas.RIGHT)
blasd.Mult(&A2, &VB, &A21, -1.0, 1.0, gomas.TRANSB, conf)
A21.Set(0, -1, be)
// A2 := (I - Y*T*Y.T).T * A2
W0.SubMatrix(&V, 0, 0, n(&A2), n(&Y2))
updateHessLeftWY(&A2, &Y1, &Y2, &T, &W0, conf)
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &A11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &t1, Tvec, util.PBOTTOM)
}
if m(&ABR) > 1 {
// do the rest with unblocked
util.Merge2x1(&A2, &ATR, &ABR)
W0.SetBuf(m(A), 1, m(A), W.Data())
unblkHessGQvdG(&A2, &tB, &W0, m(&ATR))
}
return nil
}
/*
*
* Building reduction block for blocked algorithm as described in (1).
*
* A. update next column
* a10 [(U00) (U00) ] [(a10) (V00) ]
* a11 := I -[(u10)*T00*(u10).T] * [(a11) - (v01) * T00 * a10]
* a12 [(U20) (U20) ] [(a12) (V02) ]
*
* B. compute Householder reflector for updated column
* a21, t11 := Householder(a21)
*
* C. update intermediate reductions
* v10 A02*a21
* v11 := a12*a21
* v12 A22*a21
*
* D. update block reflector
* t01 := A20*a21
* t11 := t11
*/
func unblkBuildHessGQvdG(A, T, V, W *cmat.FloatMatrix) *gomas.Error {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a10, a11, A20, a21, A22 cmat.FloatMatrix
var AL, AR, A0, a1, A2 cmat.FloatMatrix
var TTL, TTR, TBL, TBR cmat.FloatMatrix
var T00, t01, t11, T22 cmat.FloatMatrix
var VL, VR, V0, v1, V2, Y0 cmat.FloatMatrix
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, 0, 0, util.PTOPLEFT)
util.Partition2x2(
&TTL, &TTR,
&TBL, &TBR, T, 0, 0, util.PTOPLEFT)
util.Partition1x2(
&AL, &AR, A, 0, util.PLEFT)
util.Partition1x2(
&VL, &VR, V, 0, util.PLEFT)
var beta float64
for n(&VR) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&a10, &a11, nil,
&A20, &a21, &A22, A, 1, util.PBOTTOMRIGHT)
util.Repartition2x2to3x3(&TTL,
&T00, &t01, nil,
nil, &t11, nil,
nil, nil, &T22, T, 1, util.PBOTTOMRIGHT)
util.Repartition1x2to1x3(&AL,
&A0, &a1, &A2, A, 1, util.PRIGHT)
util.Repartition1x2to1x3(&VL,
&V0, &v1, &V2, V, 1, util.PRIGHT)
// ------------------------------------------------------
// Compute Hessenberg update for next column of A:
if n(&V0) > 0 {
// y10 := T00*a10 (use t01 as workspace?)
blasd.Axpby(&t01, &a10, 1.0, 0.0)
blasd.MVMultTrm(&t01, &T00, 1.0, gomas.UPPER)
// a1 := a1 - V0*T00*a10
blasd.MVMult(&a1, &V0, &t01, -1.0, 1.0, gomas.NONE)
// update a1 := (I - Y*T*Y.T).T*a1 (here t01 as workspace)
Y0.SubMatrix(A, 1, 0, n(&A00), n(&A00))
updateVecLeftWY2(&a1, &Y0, &A20, &T00, &t01, gomas.TRANS)
a10.Set(0, -1, beta)
}
// Compute Householder reflector
computeHouseholderVec(&a21, &t11)
beta = a21.Get(0, 0)
a21.Set(0, 0, 1.0)
// v1 := A2*a21
blasd.MVMult(&v1, &A2, &a21, 1.0, 0.0, gomas.NONE)
// update T
tauval := t11.Get(0, 0)
if tauval != 0.0 {
// t01 := -tauval*A20.T*a21
blasd.MVMult(&t01, &A20, &a21, -tauval, 0.0, gomas.TRANS)
// t01 := T00*t01
blasd.MVMultTrm(&t01, &T00, 1.0, gomas.UPPER)
}
// ------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, util.PBOTTOMRIGHT)
util.Continue3x3to2x2(
&TTL, &TTR,
&TBL, &TBR, &T00, &t11, &T22, T, util.PBOTTOMRIGHT)
util.Continue1x3to1x2(
&AL, &AR, &A0, &a1, A, util.PRIGHT)
util.Continue1x3to1x2(
&VL, &VR, &V0, &v1, V, util.PRIGHT)
}
A.Set(n(V), n(V)-1, beta)
return nil
}
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)
}
}
/*
* This is adaptation of TRIRED_LAZY_UNB algorithm from (1).
*/
func unblkBuildTridiagUpper(A, tauq, Y, W *cmat.FloatMatrix) {
var ATL, ABR cmat.FloatMatrix
var A00, a01, A02, a11, a12, A22 cmat.FloatMatrix
var YTL, YBR cmat.FloatMatrix
var Y00, y01, Y02, y11, y12, Y22 cmat.FloatMatrix
var tqT, tqB, tq0, tauq1, tq2 cmat.FloatMatrix
var w12 cmat.FloatMatrix
var v0 float64
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x2(
&YTL, nil,
nil, &YBR, Y, 0, 0, util.PBOTTOMRIGHT)
util.Partition2x1(
&tqT,
&tqB, tauq, 0, util.PBOTTOM)
k := 0
for k < n(Y) {
util.Repartition2x2to3x3(&ATL,
&A00, &a01, &A02,
nil, &a11, &a12,
nil, nil, &A22, A, 1, util.PTOPLEFT)
util.Repartition2x2to3x3(&YTL,
&Y00, &y01, &Y02,
nil, &y11, &y12,
nil, nil, &Y22, Y, 1, util.PTOPLEFT)
util.Repartition2x1to3x1(&tqT,
&tq0,
&tauq1,
&tq2, tauq, 1, util.PTOP)
// set temp vectors for this round
w12.SubMatrix(Y, -1, 0, 1, n(&Y02))
// ------------------------------------------------------
if n(&Y02) > 0 {
aa := blasd.Dot(&a12, &y12)
aa += blasd.Dot(&y12, &a12)
a11.Set(0, 0, a11.Get(0, 0)-aa)
// a01 := a01 - A02*y12
blasd.MVMult(&a01, &A02, &y12, -1.0, 1.0, gomas.NONE)
// a01 := a01 - Y02*a12
blasd.MVMult(&a01, &Y02, &a12, -1.0, 1.0, gomas.NONE)
// restore superdiagonal value
a12.Set(0, 0, v0)
}
// Compute householder to zero subdiagonal entries
computeHouseholderRev(&a01, &tauq1)
tauqv := tauq1.Get(0, 0)
// set sub&iagonal to unit
v0 = a01.Get(-1, 0)
a01.Set(-1, 0, 1.0)
// y01 := tauq*A00*a01
blasd.MVMultSym(&y01, &A00, &a01, tauqv, 0.0, gomas.UPPER)
// w12 := A02.T*a01
blasd.MVMult(&w12, &A02, &a01, 1.0, 0.0, gomas.TRANS)
// y01 := y01 - Y02*(A02.T*a01)
blasd.MVMult(&y01, &Y02, &w12, -tauqv, 1.0, gomas.NONE)
// w12 := Y02.T*a01
blasd.MVMult(&w12, &Y02, &a01, 1.0, 0.0, gomas.TRANS)
// y01 := y01 - A02*(Y02.T*a01)
blasd.MVMult(&y01, &A02, &w12, -tauqv, 1.0, gomas.NONE)
// beta := tauq*a01.T*y01
beta := tauqv * blasd.Dot(&a01, &y01)
// y01 := y01 - 0.5*beta*a01
blasd.Axpy(&y01, &a01, -0.5*beta)
// ------------------------------------------------------
k += 1
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &a11, &A22, A, util.PTOPLEFT)
util.Continue3x3to2x2(
&YTL, nil,
nil, &YBR, &Y00, &y11, &Y22, A, util.PTOPLEFT)
util.Continue3x1to2x1(
&tqT,
&tqB, &tq0, &tauq1, tauq, util.PTOP)
}
// restore superdiagonal value
A.Set(m(&ATL)-1, n(&ATL), v0)
}
/*
* Unblocked algorith for computing C = Q.T*C and C = Q*C.
*
* Q = H(1)H(2)...H(k) where elementary reflectors H(i) are stored on i'th column
* below diagonal in A.
*
* Progressing A from top-left to bottom-right i.e from smaller column numbers
* to larger, produces H(k)...H(2)H(1) == Q.T. and C = Q.T*C
*
* Progressing from bottom-right to top-left produces H(1)H(2)...H(k) == Q and C = Q*C
*/
func unblockedMultQLeft(C, A, tau, w *cmat.FloatMatrix, flags int) {
var ATL, ATR, ABL, ABR cmat.FloatMatrix
var A00, a10, a11, A20, a21, A22 cmat.FloatMatrix
var CT, CB, C0, c1t, C2 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2, w1 cmat.FloatMatrix
var Aref *cmat.FloatMatrix
var pAdir, pAstart, pDir, pStart util.Direction
var mb, tb, nb int
// partitioning start and direction
if flags&gomas.TRANS != 0 {
// from top-left to bottom-right to produce transposed sequence (Q.T*C)
pAstart = util.PTOPLEFT
pAdir = util.PBOTTOMRIGHT
pStart = util.PTOP
pDir = util.PBOTTOM
mb = 0
tb = 0
nb = 0
Aref = &ABR
} else {
// from bottom-right to top-left to produce normal sequence (Q*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))
tb = imax(0, tau.Len()-n(A))
Aref = &ATL
}
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, mb, nb, pAstart)
util.Partition2x1(
&CT,
&CB, C, mb, pStart)
util.Partition2x1(
&tT,
&tB, tau, tb, pStart)
for m(Aref) > 0 && n(Aref) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&a10, &a11, nil,
&A20, &a21, &A22, A, 1, pAdir)
util.Repartition2x1to3x1(&CT,
&C0,
&c1t,
&C2, C, 1, pDir)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, tau, 1, pDir)
// --------------------------------------------------------
w1.SubMatrix(w, 0, 0, c1t.Len(), 1)
applyHouseholder2x1(&tau1, &a21, &c1t, &C2, &w1, gomas.LEFT)
// --------------------------------------------------------
util.Continue3x3to2x2(
&ATL, &ATR,
&ABL, &ABR, &A00, &a11, &A22, A, pAdir)
util.Continue3x1to2x1(
&CT,
&CB, &C0, &c1t, C, pDir)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, tau, pDir)
}
}
/*
* 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 blockedMultQLeft(C, A, tau, W *cmat.FloatMatrix, flags, nb int, conf *gomas.Config) {
var ATL, ATR, ABL, ABR, AL cmat.FloatMatrix
var A00, A10, A11, A20, A21, 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 int
// partitioning start and direction
if flags&gomas.TRANS != 0 || nb == n(A) {
// from top-left to bottom-right to produce transposed sequence (Q.T*C)
pAstart = util.PTOPLEFT
pAdir = util.PBOTTOMRIGHT
pStart = util.PTOP
pDir = util.PBOTTOM
mb = 0
Aref = &ABR
} else {
// from bottom-right to top-left to produce normal sequence (Q*C)
pAstart = util.PBOTTOMRIGHT
pAdir = util.PTOPLEFT
pStart = util.PBOTTOM
pDir = util.PTOP
mb = imax(0, m(A)-n(A))
Aref = &ATL
}
util.Partition2x2(
&ATL, &ATR,
&ABL, &ABR, A, mb, 0, pAstart)
util.Partition2x1(
&CT,
&CB, C, mb, pStart)
util.Partition2x1(
&tT,
&tB, tau, 0, pStart)
transpose := flags&gomas.TRANS != 0
// intermediate reflector at start of workspace
Twork.SetBuf(nb, nb, nb, W.Data())
W0.SetBuf(n(C), nb, n(C), W.Data()[Twork.Len():])
for m(Aref) > 0 && n(Aref) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, nil, nil,
&A10, &A11, nil,
&A20, &A21, &A22, A, nb, pAdir)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, tau, nb, pDir)
bsz = n(&A11)
util.Repartition2x1to3x1(&CT,
&C0,
&C1,
&C2, C, bsz, pDir)
// --------------------------------------------------------
// clear & build block reflector from current block
util.Merge2x1(&AL, &A11, &A21)
Tw.SubMatrix(&Twork, 0, 0, bsz, bsz)
blasd.Scale(&Tw, 0.0)
unblkQRBlockReflector(&Tw, &AL, &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(&C1), bsz)
updateWithQTLeft(&C1, &C2, &A11, &A21, &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)
}
}
func blkMultLeftQL(C, A, tau, W *cmat.FloatMatrix, flags, lb int, conf *gomas.Config) {
var ATL /*ATR, ABL,*/, ABR, AL cmat.FloatMatrix
var A00, A01, A11, A22 cmat.FloatMatrix
var CT, CB, C0, C1, C2 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2 cmat.FloatMatrix
var T0, T, W0, Wrk cmat.FloatMatrix
var Aref *cmat.FloatMatrix
var pAdir, pAstart, pDir, pStart util.Direction
var mb, tb, nb int
// partitioning start and direction
if flags&gomas.TRANS != 0 {
// 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 = 0
tb = 0
nb = 0
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 = imax(0, m(A)-n(A))
nb = imax(0, n(A)-m(A))
tb = imax(0, tau.Len()-n(A))
Aref = &ABR
}
util.Partition2x2(
&ATL, nil,
nil, &ABR, A, mb, nb, pAstart)
util.Partition2x1(
&CT,
&CB, C, mb, pStart)
util.Partition2x1(
&tT,
&tB, tau, tb, pStart)
transpose := flags&gomas.TRANS != 0
// divide workspace for block reflector and temporart space
T0.SetBuf(lb, lb, lb, W.Data())
W0.SetBuf(n(C), lb, n(C), W.Data()[T0.Len():])
for n(Aref) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, nil,
nil, &A11, nil,
nil, nil, &A22, A, lb, pAdir)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2, tau, lb, pDir)
bsz := n(&A11)
util.Repartition2x1to3x1(&CT,
&C0,
&C1,
&C2, C, bsz, pDir)
// --------------------------------------------------------
// build block reflector for current block
util.Merge2x1(&AL, &A01, &A11)
T.SubMatrix(&T0, 0, 0, bsz, bsz)
blasd.Scale(&T, 0.0)
unblkQLBlockReflector(&T, &AL, &tau1)
// update with (I - Y*T*Y.T) or (I - Y*T*Y.T).T
Wrk.SubMatrix(&W0, 0, 0, n(&C1), bsz)
updateQLLeft(&C1, &C0, &A11, &A01, &T, &Wrk, transpose, conf)
// --------------------------------------------------------
util.Continue3x3to2x2(
&ATL, nil,
nil, &ABR, &A00, &A11, &A22, A, pAdir)
util.Continue3x1to2x1(
&CT,
&CB, &C0, &C1, C, pDir)
util.Continue3x1to2x1(
&tT,
&tB, &t0, &tau1, tau, pDir)
}
}
func blkMultRightQL(C, A, tau, W *cmat.FloatMatrix, flags, lb int, conf *gomas.Config) {
var ATL, ABR, AL cmat.FloatMatrix
var A00, A01, A11, A22 cmat.FloatMatrix
var CL, CR, C0, C1, C2 cmat.FloatMatrix
var tT, tB cmat.FloatMatrix
var t0, tau1, t2 cmat.FloatMatrix
var T0, T, W0, Wrk cmat.FloatMatrix
var Aref *cmat.FloatMatrix
var pAdir, pAstart, pDir, pStart, pCdir, pCstart util.Direction
var mb, tb, nb, cb int
// partitioning start and direction
if flags&gomas.TRANS != 0 {
// from top-left to bottom-right to produce transpose sequence (C*Q.T)
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)-n(A))
tb = imax(0, tau.Len()-n(A))
Aref = &ABR
} else {
// A from bottom-right to top-left to produce normal sequence (C*Q)
pAstart = util.PBOTTOMRIGHT
pAdir = util.PTOPLEFT
pStart = util.PBOTTOM
pDir = util.PTOP
pCstart = util.PRIGHT
pCdir = util.PLEFT
mb = 0
tb = 0
nb = 0
cb = 0
Aref = &ATL
}
util.Partition2x2(
&ATL, nil,
nil, &ABR /**/, A, mb, nb, pAstart)
util.Partition1x2(
&CL, &CR /**/, C, cb, pCstart)
util.Partition2x1(
&tT,
&tB /**/, tau, tb, pStart)
transpose := flags&gomas.TRANS != 0
// divide workspace for block reflector and temporary work matrix
T0.SetBuf(lb, lb, lb, W.Data())
W0.SetBuf(m(C), lb, m(C), W.Data()[T0.Len():])
for n(Aref) > 0 {
util.Repartition2x2to3x3(&ATL,
&A00, &A01, nil,
nil, &A11, nil,
nil, nil, &A22 /**/, A, lb, pAdir)
bsz := n(&A11)
util.Repartition1x2to1x3(&CL,
&C0, &C1, &C2 /**/, C, bsz, pCdir)
util.Repartition2x1to3x1(&tT,
&t0,
&tau1,
&t2 /**/, tau, bsz, pDir)
// --------------------------------------------------------
util.Merge2x1(&AL, &A01, &A11)
T.SubMatrix(&T0, 0, 0, bsz, bsz)
blasd.Scale(&T, 0.0)
unblkQLBlockReflector(&T, &AL, &tau1)
Wrk.SubMatrix(&W0, 0, 0, m(C), bsz)
updateQLRight(&C1, &C0, &A11, &A01, &T, &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)
}
}
