func createNeigboursByIdx(indices []int) (neighbors knn.Neighbors) {
for x, idx := range indices {
row := tabula.Row{}
for _, v := range dataFloat64[idx] {
rec := tabula.NewRecordReal(v)
row.PushBack(rec)
}
neighbors.Add(&row, float64(distances[x]))
}
return
}
func createNeigbours() (neighbors knn.Neighbors) {
for x, d := range dataFloat64 {
row := tabula.Row{}
for _, v := range d {
rec := tabula.NewRecordReal(v)
row.PushBack(rec)
}
neighbors.Add(&row, float64(distances[x]))
}
return
}
//
// createSynthetic will create synthetics row from original row `p` and their
// `neighbors`.
//
func (in *Runtime) createSynthetic(p *tabula.Row, neighbors knn.Neighbors) (
synthetic *tabula.Row,
) {
// choose one of the K nearest neighbors
randIdx := rand.Intn(neighbors.Len())
n := neighbors.Row(randIdx)
// Check if synthetic sample can be created from p and n.
canit, slp, sln := in.canCreate(p, n)
if !canit {
if DEBUG >= 2 {
fmt.Println("[lnsmote] can not create synthetic")
}
if slp.Len() <= 0 {
in.outliers.PushBack(p)
}
// we can not create from p and synthetic.
return nil
}
synthetic = p.Clone()
for x, srec := range *synthetic {
// Skip class attribute.
if x == in.ClassIndex {
continue
}
delta := in.randomGap(p, n, slp.Len(), sln.Len())
pv := (*p)[x].Float()
diff := (*n)[x].Float() - pv
srec.SetFloat(pv + delta*diff)
}
return
}
/*
WriteRow dump content of Row to file using format in metadata.
*/
func (writer *Writer) WriteRow(row *tabula.Row, recordMd []MetadataInterface) (
e error,
) {
nRecord := row.Len()
v := []byte{}
esc := []byte(DefEscape)
for i := range writer.OutputMetadata {
md := writer.OutputMetadata[i]
// find the input index based on name on record metadata.
rIdx, mdMatch := FindMetadata(&md, recordMd)
// No input metadata matched? skip it too.
if rIdx >= nRecord {
continue
}
// If input column is ignored, continue to next record.
if mdMatch != nil && mdMatch.GetSkip() {
continue
}
recV := (*row)[rIdx].Bytes()
lq := md.GetLeftQuote()
if "" != lq {
v = append(v, []byte(lq)...)
}
rq := md.GetRightQuote()
sep := md.GetSeparator()
// Escape the escape character itself.
if md.T == tabula.TString {
recV, _ = tekstus.BytesEncapsulate(esc, recV, esc, nil)
}
// Escape the right quote in field content before writing it.
if "" != rq && md.T == tabula.TString {
recV, _ = tekstus.BytesEncapsulate([]byte(rq), recV,
esc, nil)
} else {
// Escape the separator
if "" != sep && md.T == tabula.TString {
recV, _ = tekstus.BytesEncapsulate([]byte(sep),
recV, esc, nil)
}
}
v = append(v, recV...)
if "" != rq {
v = append(v, []byte(rq)...)
}
if "" != sep {
v = append(v, []byte(sep)...)
}
}
v = append(v, DefEOL)
_, e = writer.BufWriter.Write(v)
return e
}