From 0068854d5fede44a83b4158cacd4aaea53a16cd1 Mon Sep 17 00:00:00 2001
From: arnaucode <idoctnef@openmailbox.org>
Date: Sat, 22 Apr 2017 16:39:47 +0200
Subject: [PATCH] implemented text generation with markov chains

---
 .gitignore |  27 +++++++++++++
 README.md  |   8 ++++
 main.go    |  48 +++++++++++++++++++++++
 markov.go  | 111 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 194 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 main.go
 create mode 100644 markov.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..8cb409e
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,27 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test
+*.prof
+
+
+text.txt
diff --git a/README.md b/README.md
index 1a2b215..4f690b3 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,10 @@
 # goMarkov
 markov chains text generator written in Go from scratch
+
+
+```go
+states := markov.train(text)
+generatedText := markov.generateText(states, firstWord, count)
+fmt.Println(generatedText)
+```
+(in the text variable, goes the text content, can be loaded from a .txt file)
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..840d76c
--- /dev/null
+++ b/main.go
@@ -0,0 +1,48 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func readText(path string) (string, error) {
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		//Do something
+	}
+	dataClean := strings.Replace(string(data), "\n", " ", -1)
+	content := string(dataClean)
+	return content, err
+}
+
+func main() {
+	fmt.Print("entry the first word: ")
+	newcommand := bufio.NewReader(os.Stdin)
+	firstWord, _ := newcommand.ReadString('\n')
+	firstWord = strings.TrimSpace(firstWord)
+	fmt.Print("first word: ")
+	fmt.Println(firstWord)
+
+	fmt.Println("how many words you want on the text?")
+	newcommand = bufio.NewReader(os.Stdin)
+	answer, _ := newcommand.ReadString('\n')
+	answer = strings.TrimSpace(answer)
+	fmt.Print("Number of words on text to generate: ")
+	fmt.Println(answer)
+	count, err := strconv.Atoi(answer)
+	if err != nil {
+		fmt.Println("incorrect entry, need a positive number")
+	}
+
+	text, _ := readText("text.txt")
+
+	fmt.Println("generating text")
+	states := markov.train(text)
+	generatedText := markov.generateText(states, firstWord, count)
+	fmt.Println("")
+	fmt.Println(generatedText)
+}
diff --git a/markov.go b/markov.go
new file mode 100644
index 0000000..b6fa06d
--- /dev/null
+++ b/markov.go
@@ -0,0 +1,111 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"strconv"
+	"strings"
+)
+
+type Markov struct{}
+
+type State struct {
+	Word       string
+	Count      int
+	Prob       float64
+	NextStates []State
+}
+
+var markov Markov
+
+func addWordToStates(states []State, word string) ([]State, int) {
+	iState := -1
+	for i := 0; i < len(states); i++ {
+		if states[i].Word == word {
+			iState = i
+		}
+	}
+	if iState >= 0 {
+		states[iState].Count++
+	} else {
+		var tempState State
+		tempState.Word = word
+		tempState.Count = 1
+
+		states = append(states, tempState)
+		iState = len(states) - 1
+
+	}
+	return states, iState
+}
+
+func calcMarkovStates(words []string) []State {
+	var states []State
+	//count words
+	for i := 0; i < len(words)-1; i++ {
+		var iState int
+		states, iState = addWordToStates(states, words[i])
+		if iState < len(words) {
+			states[iState].NextStates, _ = addWordToStates(states[iState].NextStates, words[i+1])
+		}
+	}
+
+	//count prob
+	for i := 0; i < len(states); i++ {
+		states[i].Prob = (float64(states[i].Count) / float64(len(words)) * 100)
+		for j := 0; j < len(states[i].NextStates); j++ {
+			states[i].NextStates[j].Prob = (float64(states[i].NextStates[j].Count) / float64(len(words)) * 100)
+		}
+	}
+	fmt.Println("total words computed: " + strconv.Itoa(len(words)))
+	//fmt.Println(states)
+	return states
+}
+
+func textToWords(text string) []string {
+	s := strings.Split(text, " ")
+	words := s
+	return words
+}
+
+func (markov Markov) train(text string) []State {
+
+	words := textToWords(text)
+	states := calcMarkovStates(words)
+	//fmt.Println(states)
+
+	return states
+}
+
+func getNextMarkovState(states []State, word string) string {
+	iState := -1
+	for i := 0; i < len(states); i++ {
+		if states[i].Word == word {
+			iState = i
+		}
+	}
+	if iState < 0 {
+		return "word no exist on the memory"
+	}
+	var next State
+	next = states[iState].NextStates[0]
+	next.Prob = rand.Float64() * states[iState].Prob
+	for i := 0; i < len(states[iState].NextStates); i++ {
+		if (rand.Float64()*states[iState].NextStates[i].Prob) > next.Prob && states[iState-1].Word != states[iState].NextStates[i].Word {
+			next = states[iState].NextStates[i]
+		}
+	}
+	return next.Word
+}
+func (markov Markov) generateText(states []State, initWord string, count int) string {
+	var generatedText []string
+	word := initWord
+	generatedText = append(generatedText, word)
+	for i := 0; i < count; i++ {
+		word = getNextMarkovState(states, word)
+		generatedText = append(generatedText, word)
+	}
+	generatedText = append(generatedText, ".")
+	text := strings.Join(generatedText, " ")
+	return text
+}