Versuch, ein Programm zu schreiben, das die Nullstellen für ein Polynom 5. Grades und eine Konstante berechnet

Question

Diese Klasse liest Eingaben von einer JPanel-GUI. SOP nichts, es sei denn, ich gebe 1 für jeden Koeffizienten ein. Dann druckt es einfach "0.0" Irgendwelche Empfehlungen, wie ich das zum Laufen bringen kann? Ich habe alles versucht, was mir einfällt.

public class PolyRoots extends PolyGUI { 

private double coefficientToFifthPower; 
private double coefficientToFourthPower; 
private double coefficientToThirdPower; 
private double coefficientToSecondPower; 
private double coefficientToFirstPower; 
private double constant; 
private double x; 

public double getCoefficientToFifthPower() { 
    return coefficientToFifthPower; 
} 

public void setCoefficientToFifthPower(double coefficientToFifthPower) { 
    this.coefficientToFifthPower = coefficientToFifthPower; 
} 

public double getCoefficientToFourthPower() { 
    return coefficientToFourthPower; 
} 

public void setCoefficientToFourthPower(double coefficientToFourthPower) { 
    this.coefficientToFourthPower = coefficientToFourthPower; 
} 

public double getCoefficientToThirdPower() { 
    return coefficientToThirdPower; 
} 

public void setCoefficientToThirdPower(double coefficientToThirdPower) { 
    this.coefficientToThirdPower = coefficientToThirdPower; 
} 

public double getCoefficientToSecondPower() { 
    return coefficientToSecondPower; 
} 

public void setCoefficientToSecondPower(double coefficientToSecondPower) { 
    this.coefficientToSecondPower = coefficientToSecondPower; 
} 

public double getCoefficientToFirstPower() { 
    return coefficientToFirstPower; 
} 

public void setCoefficientToFirstPower(double coefficientToFirstPower) { 
    this.coefficientToFirstPower = coefficientToFirstPower; 
} 

public double getConstant() { 
    return constant; 
} 

public void setConstant(double constant) { 
    this.constant = constant; 
} 

private double y; 

public void readInputCoefficients() { 

/*  this.coefficientToFifthPower = Integer.parseInt(inputCoefficientFifthPower); 

    this.coefficientToFourthPower = Integer.parseInt(inputCoefficientFourthPower); 

    this.coefficientToThirdPower = Integer.parseInt(inputCoefficientThirdPower); 
    this.coefficientToSecondPower = Integer.parseInt(inputCoefficientSecondPower); 

    this.coefficientToFirstPower = Integer.parseInt(inputCoefficientFirstPower); 

    this.constant = Integer.parseInt(inputConstant);*/ 
} 

public double calculateY(double x) { 
    this.y = this.coefficientToFifthPower * Math.pow(x, 5) + this.coefficientToFourthPower * Math.pow(x, 4) + 
      this.coefficientToThirdPower * Math.pow(x, 3) + this.coefficientToSecondPower * Math.pow(x, 2) + (this.coefficientToFirstPower * x) + this.constant; 
    return this.y; 
} 

public void getTheBounds() { 
    for (double x = -10.0001; x <= 10.0001; x += .1) { 

     double y1 = calculateY(x); 
     double y2 = calculateY(x + .01); 

     if ((y1 * y2) < 0) { 
      System.out.println(bisectionMethod(y1, y2)); 
     } 
     else if((y1 * y2) > 0){ 
      System.out.println(bisectionMethod(y1,y2)); 
     } 
    } 

} 

public double bisectionMethod(double a, double b) { 
    double average; 
    double root = 0; 
    double yOfC; 
    int leaveloop = 0; 
    for(int x = 0; x <= 10000000; x++) { 
     average = (a + b)/2; 
     yOfC = calculateY(average); 
     if (Math.abs(yOfC) < 0.0001) { 
      root = average; 
      return root; 
     } else if (yOfC * calculateY(a) > 0) { 
      a = average; 
     } else { 
      b = average; 
     } 
    } 
    System.out.println(root); 
    return root; 
} 

}

GUI

import javax.swing.*; 
import java.awt.*; 
import java.awt.event.*; 
import java.io.IOException; 
import java.io.PrintWriter; 
import java.util.ArrayList; 
import java.util.Scanner; 

public class PolyGUI extends JPanel 
{ 
// ***Variables are created *** 
//*** GUIs are made up of JPanels. Panels are created 
//*** here and named appropriately to describe what will 
//*** be placed in each of them. 
JPanel titlePanel = new JPanel(); 
JPanel c5Panel = new JPanel(); 
JPanel c4Panel = new JPanel(); 
JPanel c3Panel = new JPanel(); 
JPanel c2Panel = new JPanel(); 
JPanel c1Panel = new JPanel(); 
JPanel cPanel = new JPanel(); 
JPanel calculatePanel = new JPanel(); 

//*** a JLabel is a text string that is given a String value 
//*** and is placed in its corresponding JPanel or JButton 
JLabel titleLabel = new JLabel(); 
JLabel c5Label = new JLabel(); 
JLabel c4Label = new JLabel(); 
JLabel c3Label = new JLabel(); 
JLabel c2Label = new JLabel(); 
JLabel c1Label = new JLabel(); 
JLabel cLabel = new JLabel(); 
JLabel questionLabel = new JLabel(); 
JLabel calculateLabel = new JLabel(); 
//*** three JButtons are created. When pushed, each button calls 
//*** its corresponding actionPerformed() method from the class created 
//*** for each button. This method executes the method code, performing 
//*** what the button is to do. 
JButton calculateButton = new JButton(); 
//*** a JTextField creates a location where the client can place 
//*** text 
JTextField x5Txt = new JTextField(8); 
JTextField x4Txt = new JTextField(8); 
JTextField x3Txt = new JTextField(8); 
JTextField x2Txt = new JTextField(8); 
JTextField xTxt = new JTextField(8); 
JTextField constantTxt = new JTextField(8); 

//*** constructor 
//*** Variables are given initial values 

public PolyGUI() 
{ 
    //*** set panel layouts 
    //*** panels could be LEFT, or RIGHT justified. 
    titlePanel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    c5Panel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    c4Panel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    c3Panel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    c2Panel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    c1Panel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    cPanel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    questionLabel.setLayout(new FlowLayout(FlowLayout.CENTER)); 
    calculateButton.setLayout(new FlowLayout(FlowLayout.CENTER)); 


    //*** set Label fonts. You can use other numbers besides 30,20 
    //*** or 15 for the font size. There are other fonts. 
    Font quizBigFont = new Font("Helvetica Bold", Font.BOLD, 30); 
    Font quizMidFont = new Font("Helvetica Bold", Font.BOLD, 20); 
    titleLabel.setFont(quizBigFont); 
    questionLabel.setFont(quizMidFont); 
    c5Label.setFont(quizMidFont); 
    c4Label.setFont(quizMidFont); 
    c3Label.setFont(quizMidFont); 
    c2Label.setFont(quizMidFont); 
    c1Label.setFont(quizMidFont); 
    cLabel.setFont(quizMidFont); 
    //*** labels are given string values 
    titleLabel.setText("Polynomial Project"); 
    questionLabel.setText("Please enter the coefficients"); 
    c5Label.setText("5"); 
    c4Label.setText("4"); 
    c3Label.setText("3"); 
    c2Label.setText("2"); 
    c1Label.setText("1"); 
    cLabel.setText("constant"); 
    calculateButton.setText("Calculate"); 
    calculateButton.addActionListener(new calculate()); 
    //*** panels 
    titlePanel.add(titleLabel); 
    c5Panel.add(c5Label); 
    c5Panel.add(x5Txt); 
    c4Panel.add(c4Label); 
    c4Panel.add(x4Txt); 
    c3Panel.add(c3Label); 
    c3Panel.add(x3Txt); 
    c2Panel.add(c2Label); 
    c2Panel.add(x2Txt); 
    c1Panel.add(c1Label); 
    c1Panel.add(xTxt); 
    cPanel.add(cLabel); 
    cPanel.add(constantTxt); 
    calculatePanel.add(calculateButton); 
    setLayout(new BoxLayout(this, BoxLayout.Y_AXIS)); 
    add(titlePanel); 
    add(questionLabel); 
    add(c5Panel); 
    add(c4Panel); 
    add(c3Panel); 
    add(c2Panel); 
    add(c1Panel); 
    add(cPanel); 
    add(calculatePanel); 


    //*** The method writeToFile() is called from the constructor. 
    //*** One could call a read method from the constructor. 

    // writeToFile(); 
}// constructor 



public void display() 
{ //*** A JFrame is where the components of the screen 
    //*** will be put. 
    JFrame theFrame = new JFrame("GUI Example"); 
    //*** When the frame is closed it will exit to the 
    //*** previous window that called it. 
    theFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
    //*** puts the panels in the JFrame 
    theFrame.setContentPane(this); 
    //*** sets the dimensions in pixels 
    theFrame.setPreferredSize(new Dimension(600, 380)); 
    theFrame.pack(); 
    //*** make the window visible 
    theFrame.setVisible(true); 
} 



class calculate implements ActionListener 
{ 
    public void actionPerformed(ActionEvent e) 
    { 
     System.out.println("Calculating..."); 
     PolyRoots p1 = new PolyRoots(); 

     double x5 = Integer.parseInt(x5Txt.getText()); 
     double x4 = Integer.parseInt(x4Txt.getText()); 
     double x3 = Integer.parseInt(x3Txt.getText()); 
     double x2 = Integer.parseInt(x2Txt.getText()); 
     double x = Integer.parseInt(xTxt.getText()); 
     double constant = Integer.parseInt(constantTxt.getText()); 

     p1.setCoefficientToFifthPower(x5); 
     p1.setCoefficientToFourthPower(x4); 
     p1.setCoefficientToThirdPower(x3); 
     p1.setCoefficientToSecondPower(x2); 
     p1.setCoefficientToFirstPower(x); 
     p1.setConstant(constant); 

     p1.getTheBounds(); 


    } 
} 


public static void main(String[] args) throws IOException 
{ 
    PolyGUI newGUI = new PolyGUI(); 
    newGUI.display(); 

} 

}

Answer 1

Hier ist ein einfaches Beispiel für ein Programm, das ein main hat und Sie können sehen, was jede Codezeile tut.

public class PolyRoots { 
    private final double[] coeffs; // any number of coefficients. 

    public PolyRoots(double... coeffs) { 
     this.coeffs = coeffs; 
    } 

    public double calcY(double x) { 
     double ret = coeffs[0]; 
     for (int i = 1; i < coeffs.length; i++) 
      ret = ret * x + coeffs[i]; 
     return ret; 
    } 

    public static void main(String[] args) { 
     PolyRoots roots = new PolyRoots(1e-3, -2e-2, 0.1, -1, 5); 
     for (int i = -10_000; i <= 10_000; i++) { 
      double x = i/1000.0; 
      double y = roots.calcY(x); 
      System.out.println(x + "\t" + y); 
     } 
    } 
} 

Um ein Programm wie dieses Sie getBounds und bisectionMethod hinzufügen können, aber diese Methode nicht das tun, was sie eigentlich (weil ich nicht herausfinden können, was sie zu tun, auch versucht, aber ich habe die Entwicklung erst seit 30 Jahre;)