feat(modules): migrate to go modules and bump go version 1.14.4

- migrate to go module
- bump go version 1.14.4

Signed-off-by: prateekpandey14 <prateek.pandey@mayadata.io>

vendor/gonum.org/v1/gonum/lapack/gonum/dlarft.go

@@ -0,0 +1,166 @@
+// Copyright ©2015 The Gonum Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gonum
+
+import (
+	"gonum.org/v1/gonum/blas"
+	"gonum.org/v1/gonum/blas/blas64"
+	"gonum.org/v1/gonum/lapack"
+)
+
+// Dlarft forms the triangular factor T of a block reflector H, storing the answer
+// in t.
+//  H = I - V * T * V^T  if store == lapack.ColumnWise
+//  H = I - V^T * T * V  if store == lapack.RowWise
+// H is defined by a product of the elementary reflectors where
+//  H = H_0 * H_1 * ... * H_{k-1}  if direct == lapack.Forward
+//  H = H_{k-1} * ... * H_1 * H_0  if direct == lapack.Backward
+//
+// t is a k×k triangular matrix. t is upper triangular if direct = lapack.Forward
+// and lower triangular otherwise. This function will panic if t is not of
+// sufficient size.
+//
+// store describes the storage of the elementary reflectors in v. See
+// Dlarfb for a description of layout.
+//
+// tau contains the scalar factors of the elementary reflectors H_i.
+//
+// Dlarft is an internal routine. It is exported for testing purposes.
+func (Implementation) Dlarft(direct lapack.Direct, store lapack.StoreV, n, k int, v []float64, ldv int, tau []float64, t []float64, ldt int) {
+	mv, nv := n, k
+	if store == lapack.RowWise {
+		mv, nv = k, n
+	}
+	switch {
+	case direct != lapack.Forward && direct != lapack.Backward:
+		panic(badDirect)
+	case store != lapack.RowWise && store != lapack.ColumnWise:
+		panic(badStoreV)
+	case n < 0:
+		panic(nLT0)
+	case k < 1:
+		panic(kLT1)
+	case ldv < max(1, nv):
+		panic(badLdV)
+	case len(tau) < k:
+		panic(shortTau)
+	case ldt < max(1, k):
+		panic(shortT)
+	}
+
+	if n == 0 {
+		return
+	}
+
+	switch {
+	case len(v) < (mv-1)*ldv+nv:
+		panic(shortV)
+	case len(t) < (k-1)*ldt+k:
+		panic(shortT)
+	}
+
+	bi := blas64.Implementation()
+
+	// TODO(btracey): There are a number of minor obvious loop optimizations here.
+	// TODO(btracey): It may be possible to rearrange some of the code so that
+	// index of 1 is more common in the Dgemv.
+	if direct == lapack.Forward {
+		prevlastv := n - 1
+		for i := 0; i < k; i++ {
+			prevlastv = max(i, prevlastv)
+			if tau[i] == 0 {
+				for j := 0; j <= i; j++ {
+					t[j*ldt+i] = 0
+				}
+				continue
+			}
+			var lastv int
+			if store == lapack.ColumnWise {
+				// skip trailing zeros
+				for lastv = n - 1; lastv >= i+1; lastv-- {
+					if v[lastv*ldv+i] != 0 {
+						break
+					}
+				}
+				for j := 0; j < i; j++ {
+					t[j*ldt+i] = -tau[i] * v[i*ldv+j]
+				}
+				j := min(lastv, prevlastv)
+				bi.Dgemv(blas.Trans, j-i, i,
+					-tau[i], v[(i+1)*ldv:], ldv, v[(i+1)*ldv+i:], ldv,
+					1, t[i:], ldt)
+			} else {
+				for lastv = n - 1; lastv >= i+1; lastv-- {
+					if v[i*ldv+lastv] != 0 {
+						break
+					}
+				}
+				for j := 0; j < i; j++ {
+					t[j*ldt+i] = -tau[i] * v[j*ldv+i]
+				}
+				j := min(lastv, prevlastv)
+				bi.Dgemv(blas.NoTrans, i, j-i,
+					-tau[i], v[i+1:], ldv, v[i*ldv+i+1:], 1,
+					1, t[i:], ldt)
+			}
+			bi.Dtrmv(blas.Upper, blas.NoTrans, blas.NonUnit, i, t, ldt, t[i:], ldt)
+			t[i*ldt+i] = tau[i]
+			if i > 1 {
+				prevlastv = max(prevlastv, lastv)
+			} else {
+				prevlastv = lastv
+			}
+		}
+		return
+	}
+	prevlastv := 0
+	for i := k - 1; i >= 0; i-- {
+		if tau[i] == 0 {
+			for j := i; j < k; j++ {
+				t[j*ldt+i] = 0
+			}
+			continue
+		}
+		var lastv int
+		if i < k-1 {
+			if store == lapack.ColumnWise {
+				for lastv = 0; lastv < i; lastv++ {
+					if v[lastv*ldv+i] != 0 {
+						break
+					}
+				}
+				for j := i + 1; j < k; j++ {
+					t[j*ldt+i] = -tau[i] * v[(n-k+i)*ldv+j]
+				}
+				j := max(lastv, prevlastv)
+				bi.Dgemv(blas.Trans, n-k+i-j, k-i-1,
+					-tau[i], v[j*ldv+i+1:], ldv, v[j*ldv+i:], ldv,
+					1, t[(i+1)*ldt+i:], ldt)
+			} else {
+				for lastv = 0; lastv < i; lastv++ {
+					if v[i*ldv+lastv] != 0 {
+						break
+					}
+				}
+				for j := i + 1; j < k; j++ {
+					t[j*ldt+i] = -tau[i] * v[j*ldv+n-k+i]
+				}
+				j := max(lastv, prevlastv)
+				bi.Dgemv(blas.NoTrans, k-i-1, n-k+i-j,
+					-tau[i], v[(i+1)*ldv+j:], ldv, v[i*ldv+j:], 1,
+					1, t[(i+1)*ldt+i:], ldt)
+			}
+			bi.Dtrmv(blas.Lower, blas.NoTrans, blas.NonUnit, k-i-1,
+				t[(i+1)*ldt+i+1:], ldt,
+				t[(i+1)*ldt+i:], ldt)
+			if i > 0 {
+				prevlastv = min(prevlastv, lastv)
+			} else {
+				prevlastv = lastv
+			}
+		}
+		t[i*ldt+i] = tau[i]
+	}
+}