main.go

package main

import (
	"bufio"
	"encoding/csv"
	"fmt"
	"log"
	"os"
	"regexp"
	"strings"
)

func getData(fileName string) []string {

	var train []string
	file, err := os.Open(fileName)

	if err != nil {
		log.Fatal(err)
	}
	defer file.Close()

	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		train = append(train, scanner.Text())
	}

	if err := scanner.Err(); err != nil {
		log.Fatal(err)
	}

	return train
}

func loadLexicon(fileName string, wordColumn byte, polarityColumn byte, polarityName string) map[string]bool {

	f, err := os.Open(fileName)
	if err != nil {
		panic(err)
	}
	defer f.Close()

	lines, err := csv.NewReader(f).ReadAll()
	if err != nil {
		panic(err)
	}

	corpse := make(map[string]bool)
	for _, line := range lines {

		if line[polarityColumn] == polarityName {
			corpse[line[wordColumn]] = true
		} else {
			corpse[line[wordColumn]] = false
		}
	}

	return corpse
}

func main() {
	//lexicon := loadLexicon(`NRC.csv`, 1, 2, `Positive`)
	lexicon := loadLexicon(`BingLiu.csv`, 0, 1, `positive`)
	data := getData("training.txt")
	regex := regexp.MustCompile(`(?m) \w+`)

	var tp, fp, tn, fn int

	for _, sentence := range data {
		var sum = 0

		for _, match := range regex.FindAllString(strings.ToLower(sentence[1:]), -1) {
			if _, found := lexicon[match[1:]]; found {
				if lexicon[match[1:]] {
					sum++
				} else {
					sum--
				}
			}
		}

		if sum >= 0 {
			if sentence[:1] == "1" {
				tp++
			} else {
				fp++
			}
		} else {
			if sentence[:1] == "0" {
				tn++
			} else {
				fn++
			}
		}
	}

	recall := float32(tp) / float32(tp+fn)
	precision := float32(tp) / float32(tp+fp)

	fmt.Println(`Recall:     `, recall)
	fmt.Println(`Precision:  `, precision)
	fmt.Println(`F1-measure: `, float32(2*recall*precision)/float32(recall+precision))

}