Merge package "github.com/shuLhan/go-mining"

1 files changed, 176 insertions, 0 deletions

diff --git a/lib/mining/classifier/stat.go b/lib/mining/classifier/stat.go
new file mode 100644
index 00000000..790aec10
--- /dev/null
+++ b/lib/mining/classifier/stat.go
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+// Copyright 2015-2016 Mhd Sulhan <ms@kilabit.info>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package classifier
+
+import (
+	"time"
+
+	"github.com/shuLhan/share/lib/dsv"
+	"github.com/shuLhan/share/lib/tabula"
+)
+
+//
+// Stat hold statistic value of classifier, including TP rate, FP rate, precision,
+// and recall.
+//
+type Stat struct {
+	// ID unique id for this statistic (e.g. number of tree).
+	ID int64
+	// StartTime contain the start time of classifier in unix timestamp.
+	StartTime int64
+	// EndTime contain the end time of classifier in unix timestamp.
+	EndTime int64
+	// ElapsedTime contain actual time, in seconds, between end and start
+	// time.
+	ElapsedTime int64
+	// TP contain true-positive value.
+	TP int64
+	// FP contain false-positive value.
+	FP int64
+	// TN contain true-negative value.
+	TN int64
+	// FN contain false-negative value.
+	FN int64
+	// OobError contain out-of-bag error.
+	OobError float64
+	// OobErrorMean contain mean of out-of-bag error.
+	OobErrorMean float64
+	// TPRate contain true-positive rate (recall): tp/(tp+fn)
+	TPRate float64
+	// FPRate contain false-positive rate: fp/(fp+tn)
+	FPRate float64
+	// TNRate contain true-negative rate: tn/(tn+fp)
+	TNRate float64
+	// Precision contain: tp/(tp+fp)
+	Precision float64
+	// FMeasure contain value of F-measure or the harmonic mean of
+	// precision and recall.
+	FMeasure float64
+	// Accuracy contain the degree of closeness of measurements of a
+	// quantity to that quantity's true value.
+	Accuracy float64
+	// AUC contain the area under curve.
+	AUC float64
+}
+
+// SetAUC will set the AUC value.
+func (stat *Stat) SetAUC(v float64) {
+	stat.AUC = v
+}
+
+//
+// SetTPRate will set TP and TPRate using number of positive `p`.
+//
+func (stat *Stat) SetTPRate(tp, p int64) {
+	stat.TP = tp
+	stat.TPRate = float64(tp) / float64(p)
+}
+
+//
+// SetFPRate will set FP and FPRate using number of negative `n`.
+//
+func (stat *Stat) SetFPRate(fp, n int64) {
+	stat.FP = fp
+	stat.FPRate = float64(fp) / float64(n)
+}
+
+//
+// SetPrecisionFromRate will set Precision value using tprate and fprate.
+// `p` and `n` is the number of positive and negative class in samples.
+//
+func (stat *Stat) SetPrecisionFromRate(p, n int64) {
+	stat.Precision = (stat.TPRate * float64(p)) /
+		((stat.TPRate * float64(p)) + (stat.FPRate * float64(n)))
+}
+
+//
+// Recall return value of recall.
+//
+func (stat *Stat) Recall() float64 {
+	return stat.TPRate
+}
+
+//
+// Sum will add statistic from other stat object to current stat, not including
+// the start and end time.
+//
+func (stat *Stat) Sum(other *Stat) {
+	stat.OobError += other.OobError
+	stat.OobErrorMean += other.OobErrorMean
+	stat.TP += other.TP
+	stat.FP += other.FP
+	stat.TN += other.TN
+	stat.FN += other.FN
+	stat.TPRate += other.TPRate
+	stat.FPRate += other.FPRate
+	stat.TNRate += other.TNRate
+	stat.Precision += other.Precision
+	stat.FMeasure += other.FMeasure
+	stat.Accuracy += other.Accuracy
+}
+
+//
+// ToRow will convert the stat to tabula.row in the order of Stat field.
+//
+func (stat *Stat) ToRow() (row *tabula.Row) {
+	row = &tabula.Row{}
+
+	row.PushBack(tabula.NewRecordInt(stat.ID))
+	row.PushBack(tabula.NewRecordInt(stat.StartTime))
+	row.PushBack(tabula.NewRecordInt(stat.EndTime))
+	row.PushBack(tabula.NewRecordInt(stat.ElapsedTime))
+	row.PushBack(tabula.NewRecordReal(stat.OobError))
+	row.PushBack(tabula.NewRecordReal(stat.OobErrorMean))
+	row.PushBack(tabula.NewRecordInt(stat.TP))
+	row.PushBack(tabula.NewRecordInt(stat.FP))
+	row.PushBack(tabula.NewRecordInt(stat.TN))
+	row.PushBack(tabula.NewRecordInt(stat.FN))
+	row.PushBack(tabula.NewRecordReal(stat.TPRate))
+	row.PushBack(tabula.NewRecordReal(stat.FPRate))
+	row.PushBack(tabula.NewRecordReal(stat.TNRate))
+	row.PushBack(tabula.NewRecordReal(stat.Precision))
+	row.PushBack(tabula.NewRecordReal(stat.FMeasure))
+	row.PushBack(tabula.NewRecordReal(stat.Accuracy))
+	row.PushBack(tabula.NewRecordReal(stat.AUC))
+
+	return
+}
+
+//
+// Start will start the timer.
+//
+func (stat *Stat) Start() {
+	stat.StartTime = time.Now().Unix()
+}
+
+//
+// End will stop the timer and compute the elapsed time.
+//
+func (stat *Stat) End() {
+	stat.EndTime = time.Now().Unix()
+	stat.ElapsedTime = stat.EndTime - stat.StartTime
+}
+
+//
+// Write will write the content of stat to `file`.
+//
+func (stat *Stat) Write(file string) (e error) {
+	if file == "" {
+		return
+	}
+
+	writer := &dsv.Writer{}
+	e = writer.OpenOutput(file)
+	if e != nil {
+		return e
+	}
+
+	e = writer.WriteRawRow(stat.ToRow(), nil, nil)
+	if e != nil {
+		return e
+	}
+
+	return writer.Close()
+}