I am trying to make this input.txt into a 2D array. I tried a few different methods. This is my latest attempt, and I seem to be stuck here... Any help is much appreciated.
input.txt structure: SCI2000/Science/1200/10/C --> There are 23 rows and 5 columns. I'd also like to have a title made for each column.
FileReader fr = new FileReader("input.txt");
BufferedReader br = new BufferedReader(fr);
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
sb.append(line);
sb.append(System.lineSeparator());
line = br.readLine();
}
String everything = sb.toString();
String[][] input = new String[23][5];
String[] tokens = everything.split("/");
for(String str : tokens)
System.out.print(str);
Just the main processing part (not tested):
int columns = 5;
String[] row = String[columns];
int j = 0;
while ((line = br.readline) != null) {
row = line.split("/");
for(int i=0; i<row.length; ++i) {
input[j,i] = row(i);
}
++j;
}
FileReader fr = new FileReader("input.txt");
BufferedReader br = new BufferedReader(fr);
String[][] input = new String[24][5]; // 1 row for title, 23 rows for data
// add title
input[0] = new String[]{"title1", "title1", "title1", "title1", "title1"};
String line = br.readLine();
int row = 1; // update here
while ( (line = br.readLine())!= null ) {
input[row++] = line.split("/");
}
// print all data
for ( int i = 0; i < input.length; i++) {
for ( int j = 0; j < input[i].length; j++ )
System.out.print(input[i][j] + " ");
//new line
System.out.println();
}
Related
I am trying to find top k words in a "data" text file. But I cannot remove stopwords including in "stop.txt" should I do it manually adding stopwords one by one or there is a method to read stop.txt file and remove these words in data.txt file?
try {
System.out.println("Enter value of 'k' words:: ");
Scanner in = new Scanner(System.in);
int n = in.nextInt();
w = new String[n];
r = new int[n];
Set<String> stopWords = new LinkedHashSet<String>();
BufferedReader SW = new BufferedReader(new FileReader("stop.txt"));
for(String line; (line = SW.readLine()) != null;)
stopWords.add(line.trim());
SW.close();
FileReader fr = new FileReader("data.txt");
BufferedReader br = new BufferedReader(fr);
String text = "";
String sz = null;
while((sz=br.readLine())!=null){
text = text.concat(sz);
}
String[] words = text.split(" ");
String[] uniqueLabels;
int count = 0;
uniqueLabels = getUniqLabels(words);
for(int j=0; j<n; j++){
r[j] = 0;
}
for(String l: uniqueLabels)
{
if("".equals(l) || null == l)
{
break;
}
for(String s : words)
{
if(l.equals(s))
{
count++;
}
}
for(int i=0; i<n; i++){
if(count>r[i]){
r[i] = count;
w[i] = l;
break;
}
}
count=0;
}
display(n);
} catch (Exception e) {
System.err.println("ERR "+e.getMessage());
}
Read file contents by:
List<String> stopwords = Files.readAllLines(Paths.get("english_stopwords.txt"));
Then use this for removing stop words:
ArrayList<String> allWords =
Stream.of(original.toLowerCase().split(" "))
.collect(Collectors.toCollection(ArrayList<String>::new));
allWords.removeAll(stopwords);
String result = allWords.stream().collect(Collectors.joining(" "));
Removing Stopwords from a String in Java
I have a .txt file that contains text that I would like to save part of it in a String, part of it in a String array, and then the last part in a 2D int array, and am faced with two issues:
How to read and save both of the arrays when their size is not known ahead of time?
2D array is not reading/saving properly
Here is the text file for reference:
This is the sentence to be read.
This
is
a
String
array.
90 47 110 95 95
101 87
54 0 38 12
Here is part of my method that is supposed to read and save the three data types:
BufferedReader br = new BufferedReader(new FileReader(fileName));
sentence = br.readLine();
stringArr = new String[5]; //how to initialize without set number of elements?
for(int i = 0; i<stringArr.length; i++){
stringArr[i] = br.readLine();
}
int2DArr = new int[3][5]; //how to initialize with any amount of rows and columns?
for(int i = 0; i<int2DArr.length; i++){
for(int j = 0; j<int2DArr[i].length; j++){
int2DArr[i][j] = br.read();
//how to read the space after each int ?
}
}
How would I "grab" the size of the arrays by reading the text file, so that when I initialize both arrays, I have the proper sizes? Any help would be greatly appreciated!
Instead of trying to achieve everything in a single pass we can pass through the file twice and obtain a neater code.
It will consume double time of course but it is going to help you understand how you could break bigger problems into smaller ones and deal with them one by one.
Here are the steps:
Determine size of stringArr and intArr in first pass
Fill value in respective array in second pass
If you are wondering how no of columns for int2DArr is determine. Simply we don't do it our self. We use the concept of Jagged Arrays
Read more here How do I create a jagged 2d array in Java?
import java.util.*;
import java.io.*;
class ReadFileIntoArr {
public static void main(String args[]) throws IOException {
String fileName = "test.txt";
BufferedReader br = new BufferedReader(new FileReader(fileName));
String line = br.readLine();
int strSize = 0;
int intSize = 0;
boolean isDigit = false;
while (line != null && line.trim().length() != 0) {
if (!isDigit && Character.isDigit(line.charAt(0)))
isDigit = true;
if (isDigit)
intSize++;
else
strSize++;
line = br.readLine();
}
br = new BufferedReader(new FileReader(fileName));
String[] stringArr = new String[strSize];
for (int i = 0; i < stringArr.length; i++)
stringArr[i] = br.readLine();
int[][] int2DArr = new int[intSize][];
for (int i = 0; i < int2DArr.length; i++)
int2DArr[i] = Arrays.stream(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
System.out.println(Arrays.toString(stringArr));
System.out.println(Arrays.deepToString(int2DArr));
}
}
Note: In single pass this could be accomplished with the help of ArrayList and later transfer everything into respective array.
Update: After understanding the constraints for your problem here is another version
import java.util.*;
import java.io.*;
class ReadFileIntoArr {
public static void main(String args[]) throws IOException {
String fileName = "test.txt";
BufferedReader br = new BufferedReader(new FileReader(fileName));
String line = br.readLine();
int strSize = 0;
int intSize = 0;
boolean isDigit = false;
while (line != null && line.trim().length() != 0) {
if (!isDigit && isDigit(line.charAt(0)))
isDigit = true;
if (isDigit)
intSize++;
else
strSize++;
line = br.readLine();
}
br = new BufferedReader(new FileReader(fileName));
String[] stringArr = new String[strSize];
for (int i = 0; i < stringArr.length; i++)
stringArr[i] = br.readLine();
int[][] int2DArr = new int[intSize][];
for (int i = 0; i < int2DArr.length; i++)
int2DArr[i] = convertStringArrToIntArr(br.readLine().split(" "));
System.out.println(Arrays.toString(stringArr));
System.out.println(Arrays.deepToString(int2DArr));
}
public static boolean isDigit(char c) {
return c >= '0' && c <= '9';
}
public static int[] convertStringArrToIntArr(String[] strArr) {
int[] intArr = new int[strArr.length];
for (int i = 0; i < strArr.length; i++)
intArr[i] = Integer.parseInt(strArr[i]);
return intArr;
}
}
Path path = Paths.get(fileName);
List<String> lines = Files.readAllLines(path, Charset.defaultCharset());
String title = lines.get(0);
List<String> words = new ArrayList<>();
for (int i = 1; i < lines.size(); ++i) {
String word = lines.get(i);
if (!word.isEmpty() && Character.isDigit(word.codePointAt(0)) {
break;
}
words.add(word);
}
String[] wordArray = words.toArray(new String[]);
int i0 = 1 + words.size();
int n = lines.size() - i0;
int[][] numbers = new int[n][];
for (int i = i0; i < lines.size(); ++i) {
String[] values = lines.get(i).trim().split("\\s+");
int m = values.length;
int[] row = new int[m];
for (int j = 0; j < m; ++m) {
row[j] = Integer.parse(values[j]);
}
numbers[i - i0] = row;
}
Path is a generalisation of File, also URLs.
Files is a treasure trove of file functions.
One could do without dynamically sized List; one would need to test first,
but normally one would use a List anyhow.
String.split splits on one or more whitespace.
i have n cols and m rows in a specific file how i can but each col in a different array ?
*the number of rows and cols are changeable
String readline = null;
readline = read.readLine();
String[] getlength = readline.split(" ");
cols = getlength.length;
while (readline != null) {
readline = read.readLine();
rows++;
}
// Array of data
int[][] data = new int[rows][cols];
// New bufferedReader to put the cursor on the top of the file
read = new BufferedReader(new FileReader("1.txt"));
// for loop to skip first three rows
for (int i = 1; i <= 3; i++) {
read.readLine();
}
// to set the file Data into the array
String line = null;
line = read.readLine();
do {
readData = line.split(" ");
for (int j = 0; j < readData.length; j++) {
data[indexx][j] = Integer.parseInt(readData[j]);
}
indexx++;
line = read.readLine();
} while (line != null);
If you don't know the number of columns in the table you are reading you should use an ArrayList. One possible way would be:
[...]
ArrayList result = new ArrayList<int[]>();
line = read.readLine();
do {
readData = line.split(" ");
int[] row = new int[readData.length];
for(int i = 0; i < readData.length; i++) {
row[i] = Integer.parseInt(readData[i]);
}
result.add(row);
} while (line != null);
Now if you need your result as an array you can do the following conversion:
int[] data = result.toArray(new int[result.size()]);
I have code successfully reading from a CSV. However when I try to use fileReader to read a solo line, it makes my code stop working.
Here is my code:
try {
String line = "";
fileReader = new BufferedReader(new FileReader(filename));
while ((line = fileReader.readLine()) != null) {
String[] tokens = line.split(DELIMITER);
for (String token : tokens) {
totalData.add(token);
if (!artists.contains(token)) {
artists.add(token);
}
}
for (int l = 0; l <= 999; l++) {
lineData = fileReader.readLine();
lineArray[l] = lineData;
}
}
} finally {
fileReader.close();
}
When I try to read arrayList sizes and print data I get from the arrayLists above this code below makes it stop working:
for (int l = 0; l <= 80; l++) {
lineData = fileReader.readLine();
lineArray[l] = lineData;
}
If I comment this for loop, everything is fine. I really need this for loop, how can I edit my code to resolve this issue? Also, what is happening?
for (int l = 0; l <= 80; l++) {
lineData = fileReader.readLine();
lineArray[l] = lineData;
}
This hard code can replace a single line of code:
lineArray[i++] = line;
I corrected your code and that's what happened:
String line = "";
int i = 0;
try (BufferedReader fileReader = new BufferedReader(new FileReader(""))) {
while ((line = fileReader.readLine()) != null) {
lineArray[i++] = line;
String[] tokens = line.split(DELIMITER);
for (String token : tokens) {
totalData.add(token);
if (!artists.contains(token)) {
artists.add(token);
}
}
}
}
example i have this numbers or arrays on my file (notepad)
2 3 4 5 7 2 6 2
2 4 6 8 9 4 8 1
I want to ask if how to read the next row. I can only read the first row using this code.
String path = "/path/notepad.txt";
String stringOfNumbers[];
BufferedReader br = new BufferedReader (new InputStreamReader(System.in));
BufferedReader br2 = new BufferedReader (new FileReader(path));
String lineOfNumbers = br2.readLine();
stringOfNumbers = lineOfNumbers.split(" ");
//stringOfNumbers = lineOfNumbers.split("\n");
String str = lineOfNumbers.replace(","," ");
System.out.println(str);
System.out.print("");
int numbers[][] = new int [stringOfNumbers.length][stringOfNumbers.length];
for (int i = 0; i < numbers.length; i++)
{
numbers[i][i] = Integer.parseInt(stringOfNumbers[i]);
}
System.out.print("Enter the number to search: ");
int searchNumber = Integer.parseInt(br.readLine());
int location = 0;
for (int i = 0; i < numbers.length; i++)
{
if (numbers[i][i] == searchNumber)
{
location = i+ 1;
}
}
thank you in advance.
I would do somethin like this
FileReader fr = new FileReader("myFileName");
BufferedReader br = new BufferedReader(fr);
while((line=br.readLine())!=null) // as long as there are lines in the file
{
stringOfNumbers = line.split(" ");
// other code
}
Following code will Help you save all numbers in a file to memory
Scanner scanner = new Scanner(path);
List<Integer[]> integerArList = new ArrayList<Integer[]>();
while(scanner.hasNextLine()){
String lineOfNumbers = scanner.nextLine();
stringOfNumbers = lineOfNumbers.split(" ");
//stringOfNumbers = lineOfNumbers.split("\n");
String str = lineOfNumbers.replace(","," ");
System.out.println(str);
System.out.print("");
Integer[] numbers = new Integer[stringOfNumbers.length];
for (int i = 0; i < numbers.length; i++)
{
numbers[i] = Integer.parseInt(stringOfNumbers[i]);
}
integerArList.add(numbers);
}
After this you can search any Integer by traversing each array in the List like this:
int searchMe = <get this from user>
int location=0;
boolean found=false;
for(Integer[] intAr: integerArList){
for(int i=0;i<intAr.length;i++){
if(intAr[i]==searchMe){
location+=(i+1)
found=true;
break;
}
}
if(found) break;
location+=intAr.length;
}
System.out.println("Location of " + searchMe +" : " +(found?location:"Not Found in Data"));
Hope this helps.
To read all lines of a text file you can do something like this:
String path = "/path/notepad.txt";
String stringOfNumbers[];
BufferedReader br = new BufferedReader (new InputStreamReader(System.in));
BufferedReader br2 = new BufferedReader (new FileReader(path));
ArrayList<String> listOfLines = new ArrayList<String>();
//String lineOfNumbers = "";
String line = "";
String allIndexes = "";
while ((line = br2.readLine()) != null) {
if(!line.isEmpty()){
listOfLines.add(line);
}
}
for(String lineOfNumbers : listOfLines){
stringOfNumbers = lineOfNumbers.split(" ");
//stringOfNumbers = lineOfNumbers.split("\n");
String str = lineOfNumbers.replace(","," ");
System.out.println(str);
System.out.print("");
int numbers[][] = new int [stringOfNumbers.length][listOfLines.size()];
for (int i = 0; i < numbers.length; i++)
{
numbers[i][listOfLines.indexOf(lineOfNumbers)] = Integer.parseInt(stringOfNumbers[i]);
}
System.out.print("Enter the number to search: ");
int searchNumber = Integer.parseInt(br.readLine());
int locationI = 0;
int locationJ = 0;
for (int i = 0; i < numbers.length; i++)
{
for(int j = 0; j < listOfLines.size(); j++)
if (numbers[i][j] == searchNumber)
{
locationI = i + 1;
locationJ = j + 1;
allIndexes += locationI + ":" + locationJ + " ";
}
}
}