Getting specific column from text file into an array - arrays

What I need to achieve is to import data from a text file that contains two columns of doubles as follows:
201.0176 1.06E+03
201.7557 1.11E+01
202.0201 2.02E+02
202.2064 9.76E+00
202.8342 1.11E+01
203.0161 2.02E+02
203.1638 9.61E+00
203.3843 1.13E+01
There are up to about 50,000 lines of these data. I want each column to be imported into a separate array but I cannot work out how to identify between the separate columns. I have tried the following:
public class CodeTests {
public static ArrayList assignArray(String filePath) throws FileNotFoundException {
Scanner s = new Scanner(new File(filePath));
ArrayList<Double> list = new ArrayList<Double>();
while (s.hasNext()){
list.add(s.nextDouble());
}
s.close();
return list;
}
public static void main(String[] args) throws IOException {
/*
*
*/
ArrayList arrayMZ;
arrayMZ = assignArray("F:/Stuff/Work/Work from GSK/From Leeds/ja_CIDFragmenter/testFile.txt");
for(int i = 0; i < arrayMZ.size(); i++)
System.out.println(arrayMZ.get(i));
System.out.println("End");
}
}
From running this I get the output:
run:
201.0176
1060.0
201.7557
11.1
202.0201
202.0
202.2064
9.76
202.8342
11.1
203.0161
202.0
203.1638
9.61
203.3843
11.3
End
BUILD SUCCESSFUL (total time: 1 second)
Can anyone help me either separate these columns into two arrays or even into a single 2D array under the columns of array[0] with the first data column in it and array[1] with the second. i.e. :
[0] [1]
201.0176 1.06E+03
201.7557 1.11E+01
202.0201 2.02E+02
202.2064 9.76E+00
202.8342 1.11E+01
203.0161 2.02E+02
203.1638 9.61E+00
203.3843 1.13E+01
I've tried to make this as clear as I can but if there is anything else please let me know.
Thanks

You could do something like this:
public static ArrayList[] assignArray(String filePath) throws FileNotFoundException {
Scanner s = new Scanner(new File(filePath));
ArrayList[] list = new ArrayList[2];
ArrayList<Double> col1 = new ArrayList<Double>();
ArrayList<Double> col2 = new ArrayList<Double>();
while (s.hasNext()){
String[] data = s.nextLine().split("\\s+");
col1.add(Double.parseDouble(data[0]));
col2.add(Double.parseDouble(data[1]));
}
s.close();
list[0] = col1;
list[1] = col2;
return list;
}
and obtain an array of two ArrayList with your data.

Something like:
for(int i = 0; i < arrayMZ.size() / 2; i+=2)
System.out.printf("%.4f\t%E\n", arrayMZ.get(i), arrayMZ.get(i + 1));

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How to fix method printing null for some iterations?

Write a program that shall calculate the vocabulary richness of a text in a file and the frequency of the most common word. The vocabulary richness is the number of words in the text divided by the number of distinct words. The frequency of a word is the number of times the word is mentioned in the text divided by the total number of words in the text.
Define and implement class WordCounter with two private fields String word and int count, constructor WordCounter(String word), and public methods String getName(), int getCount(), and void addToCounter().
Define and implement class Corpus (as in text corpus) with one private field ArrayList<WordCounter> words, constructor Corpus(BufferedReader infile), and public methods double getVocabularyRichness() and String getMostFrequentWord().
Implement a test program (as the public static void main method in Corpus) that reads all files in a specific folder, creates a Corpus object from each (previously opened) file, and saves the requested statistics into another file stats.csv. You can either create a new Corpus object for each file or define an ArrayList<Corpus> of the corpora.
Each line of the CSV file must consist of three fields separated by commas (but no spaces!): the file name, the vocabulary richness, and the most frequently used word. Run your program on all Shakespeare's plays. Submit the CSV file together with the Java file.
I wrote what I think is the correct implementation of the HW problem because it works properly for some of the text files, however only the words.get(i).getName() (I tested with words.get(i).getCount()) method will print a blank space for some of the files. I have tried everything, and can't seem to figure it out. Can you please give me a hint or some guidance as to how to fix this issue?
public class Corpus {
private ArrayList<WordCounter> words = new ArrayList <WordCounter>() ;
Corpus(BufferedReader infile){
String ln;
try {
while((ln = infile.readLine()) != null) {
for (String word : ln.toLowerCase().split("([,.\\s]+)")) {
int reference = 0;
for(int i = 0; i < words.size(); i++) {
if (word.equals(words.get(i).getName())) {
reference++;
words.get(i).addToCounter();
} }
if (reference==0) { words.add(new WordCounter(word)); }
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
public double getVocabularyRichness() {
int word_count=0;
for(int i = 0; i < words.size(); i++) {
word_count=word_count+words.get(i).getCount();
}
return (double)word_count/(double)words.size();
}
public String getMostFrequentWord() {
String winner = "*AN ERROR OCCURRED*";
int max_count = 0;
for(int i = 0; i < words.size(); i++) {
if(words.get(i).getCount() > max_count){
max_count = words.get(i).getCount();
}
}
for(int i = 0; i < words.size(); i++) {
if(words.get(i).getCount() == max_count){
winner = words.get(i).getName();
}
}
//winner="Test " + String.valueOf(words.get(i).getName());;
//return String.valueOf(max_count);
return winner;
}
public static void main(String [] args) throws Exception{
BufferedWriter writer = null;
File folder_location = new File("/Users/joaquindelaguardia/Desktop/Shakespeare");
File[] file_array = folder_location.listFiles();
for(File iteration_file: file_array) {
FileReader current_file = new FileReader(iteration_file);
BufferedReader infile = new BufferedReader(current_file);
Corpus obj1 = new Corpus(infile);
String file_name = iteration_file.getName();
String frequent_word = obj1.getMostFrequentWord();
String vocabulary_richness = String.valueOf(obj1.getVocabularyRichness());
System.out.println(file_name);
System.out.println(frequent_word);
System.out.println(vocabulary_richness);
System.out.println("-----------------------------");
//FileWriter file_writer = new FileWriter("/Users/joaquindelaguardia/Desktop/stats.csv");
//writer = new BufferedWriter(file_writer);
//String output = file_name+", "+frequent_word+", "+vocabulary_richness + "\n";
//writer.append(output);
}
//writer.close();
}
}
public class WordCounter {
private String word;
private int count=1;
WordCounter(String word){
this.word=word;
}
public String getName() {
return word;
}
public int getCount() {
return count;
}
public void addToCounter() {
count++;
}
}
Im testing the information by printing before appending to file, and as you can see with the small fragment of the output included below, for some cases it prints the most common word (and) while in the second case it doesn't print anything.
shakespeare-lovers-62.txt
and
2.2409948542024014
shakespeare-julius-26.txt
6.413205537806177

How can I create a loop to randomly assign values to each characteristic of an array of class instances

So I am creating a card game that requires different cards, so I created a card class in which I declared the string value names and other integer values that are the powers eg. Intelligence
public static class hero{
static String name;
static int strength;
static int intellect;
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So I created an array of instances of these classes.
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This is what I've done so far
public static void readLines(File f)throws IOException{
FileReader fr = new FileReader(f);
BufferedReader br = new BufferedReader(fr);
String line;
while((line = br.readLine()) != null){
System.out.println(line);
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br.close();
fr.close();
}
static File f = new File("C:/Users/jeff/Desktop/test/names.txt");
try{
readLines(f);
} catch (IOException e){
e.printStackTrace();
}
Q2)The part I am also having trouble with is the part where I need to create a loop to randomly assign values to each power of each instance of a class.
Here's what I've done so far
{
hero [] cards = new hero[cardNumber];
for(int i=4;i<cardNumber;i++){ cards[i]=new hero();}
Random rand = new Random();
for(int i=0; i<cards.length; ++i)
{
cards[i].strength = rand.nextInt(25) + 1;
cards[i].intellect = rand.nextInt(25) + 1;
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But when I print out the values all the instances have the same value for their powers.
Eg Card 12 Intelligence = 6
And Card 14 Intelligence = 6
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java.io.FileNotFoundException occurs

I am trying to run the below code, but error occurs,The filename I mentioned is present on the given path.
public class DataDriventc {
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File f = new File("‪C:/Users/Avnish/Desktop/Input.xlsx");
Workbook w = Workbook.getWorkbook(f);
Sheet s = w.getSheet("Sheet1");
int columns = s.getColumns();
int rows = s.getRows();
System.out.println(columns + "," + rows);
}
}
Try this:
File f = new File("‪C:\\Users\\Avnish\\Desktop\\Input.xlsx");
For reference, see this question.

how can i store a text file into an array?

so that later i can parse the array and if the line contains 3 doubles store it into an array of object type? ill later have to store the lines with 3 doubles into another array.
here's an example of my code so far
public static void readFile(){
Scanner scnr = null;
File info = new File("info.txt");
try {
scnr = new Scanner(info);
} catch (FileNotFoundException e) {
System.out.println("file not found");
e.printStackTrace();
}
int counterLines = 0;
String nextLine = "";
while(scnr.hasNextLine()){
nextLine = scnr.nextLine();
counterLines ++;
}
System.out.println(counterLines);
String[] infoArray = new String[counterLines];
for(int i = 0; i < counterLines; i++){
infoArray[i] = scnr.nextLine();
System.out.println(infoArray[i]);
You can probably spilt the text of the file into individual words using String.split() which gives you a String array.

Processing: assign a value to each object in an array?

Sorry this is probably a dumb question. I'm kinda new to coding and I'm using Processing, which is based off Java.
I have an array of 5 rectangle objects in my main program
for (int i = 0; i < portals.length; i++)
{
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when displayed, I call this method from my Portals class
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rect(xLoc, yLoc, rad, 30);
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int xLoc;
int yLoc;
String name;
...
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this.name = name;
}
public String getName(){
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Then you can try to access by name in array
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}
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Or you can use a Map. But that may be more advanced than your knowledge, so I won't give code. But that's another suggestion.
Edit: with Map
Map<String, Portals> map = new HashMap<String, Portals>();
Key Value
map.put("nameForPortal", new Portals());
map.put("anotherNameForPortal", new Portals());
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Portals p = map.get("nameForPortal");

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