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f8c9938d62
# The first commit's message is: fix merge # The 2nd commit message will be skipped: # Add Dgesvd and test # The 3rd commit message will be skipped: # implemented work thing
113 lines
3.4 KiB
Go
113 lines
3.4 KiB
Go
// Copyright ©2015 The gonum Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package native
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import (
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"math"
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"github.com/gonum/lapack"
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)
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// Implementation is the native Go implementation of LAPACK routines. It
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// is built on top of calls to the return of blas64.Implementation(), so while
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// this code is in pure Go, the underlying BLAS implementation may not be.
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type Implementation struct{}
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var _ lapack.Float64 = Implementation{}
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// This list is duplicated in lapack/cgo. Keep in sync.
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const (
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absIncNotOne = "lapack: increment not one or negative one"
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badD = "lapack: d has insufficient length"
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badDecompUpdate = "lapack: bad decomp update"
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badDiag = "lapack: bad diag"
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badDims = "lapack: bad input dimensions"
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badDirect = "lapack: bad direct"
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badE = "lapack: e has insufficient length"
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badIpiv = "lapack: insufficient permutation length"
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badLdA = "lapack: index of a out of range"
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badNorm = "lapack: bad norm"
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badPivot = "lapack: bad pivot"
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badS = "lapack: s has insufficient length"
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badSide = "lapack: bad side"
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badSlice = "lapack: bad input slice length"
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badStore = "lapack: bad store"
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badTau = "lapack: tau has insufficient length"
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badTauQ = "lapack: tauQ has insufficient length"
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badTauP = "lapack: tauP has insufficient length"
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badTrans = "lapack: bad trans"
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badUplo = "lapack: illegal triangle"
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badWork = "lapack: insufficient working memory"
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badWorkStride = "lapack: insufficient working array stride"
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badZ = "lapack: insufficient z length"
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kGTM = "lapack: k > m"
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kGTN = "lapack: k > n"
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kLT0 = "lapack: k < 0"
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mLTN = "lapack: m < n"
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negDimension = "lapack: negative matrix dimension"
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negZ = "lapack: negative z value"
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nLT0 = "lapack: n < 0"
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nLTM = "lapack: n < m"
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shortWork = "lapack: working array shorter than declared"
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)
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// checkMatrix verifies the parameters of a matrix input.
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func checkMatrix(m, n int, a []float64, lda int) {
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if m < 0 {
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panic("lapack: has negative number of rows")
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}
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if m < 0 {
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panic("lapack: has negative number of columns")
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}
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if lda < n {
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panic("lapack: stride less than number of columns")
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}
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if len(a) < (m-1)*lda+n {
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panic("lapack: insufficient matrix slice length")
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}
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}
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func checkVector(n int, v []float64, inc int) {
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if n < 0 {
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panic("lapack: negative matrix length")
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}
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if (inc > 0 && (n-1)*inc >= len(v)) || (inc < 0 && (1-n)*inc >= len(v)) {
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panic("lapack: insufficient vector slice length")
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}
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}
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func min(a, b int) int {
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if a < b {
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return a
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}
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return b
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}
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func max(a, b int) int {
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if a > b {
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return a
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}
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return b
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}
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var (
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// dlamchE is the machine epsilon. For IEEE this is 2^-53.
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dlamchE = 1.0 / (1 << 53)
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// dlamchP is 2 * eps
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dlamchP = 2 * dlamchE
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// dlamchS is the "safe min", that is, the lowest number such that 1/sfmin does
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// not overflow. The Netlib code for calculating this number is not correct --
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// it overflows. Found by comparison with the FORTRAN value.
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dlamchS = math.Nextafter((4 / math.MaxFloat64), 0)
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smlnum = dlamchS / dlamchP
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bignum = 1 / smlnum
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// dlamchB is the radix of the machine (the base of the number system).
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dlamchB = 2
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)
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