在我的功能中，我有：
"""
Iterates 300 times as attempts, each having an inner-loop
to calculate the z of a neighboring point and returns the optimal
"""
pointList = []
max_p = None
for attempts in range(300):
neighborList = ( (x - d, y), (x + d, y), (x, y - d), (x, y + d) )
for neighbor in neighborList:
z = evaluate( neighbor[0], neighbor[1] )
point = None
point = Point3D( neighbor[0], neighbor[1], z)
pointList += point
max_p = maxPoint( pointList )
x = max_p.x_val
y = max_p.y_val
return max_p
我没有迭代我的类实例，指出，但我仍然得到：
pointList += newPoint
TypeError: 'Point3D' object is not iterable
答案 0 :(得分：5)
问题在于这一行：
leftDoc right是import java.awt.EventQueue;
import java.awt.GridLayout;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.PlainDocument;
public class MirrorTextAreas {
public static void main(String[] args) {
new MirrorTextAreas();
}
public MirrorTextAreas() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
JTextArea left = new JTextArea(10, 20);
JTextArea right = new JTextArea(10, 20);
setLayout(new GridLayout(1, 2));
add(new JScrollPane(left));
add(new JScrollPane(right));
MirrorDocument leftDoc = new MirrorDocument();
MirrorDocument rightDoc = new MirrorDocument();
left.setDocument(leftDoc);
right.setDocument(rightDoc);
leftDoc.addDocumentListener(new DocumentHandler(rightDoc));
rightDoc.addDocumentListener(new DocumentHandler(leftDoc));
}
}
public class MirrorDocument extends PlainDocument {
private boolean ignoreUpdates;
public void setIgnoreUpdates(boolean ignoreUpdates) {
this.ignoreUpdates = ignoreUpdates;
}
public boolean isIgnoreUpdates() {
return ignoreUpdates;
}
}
public static class DocumentHandler implements DocumentListener {
private MirrorDocument slaveDocument;
private boolean ignoreUpdates = false;
public DocumentHandler(MirrorDocument slaveDocument) {
this.slaveDocument = slaveDocument;
}
@Override
public void insertUpdate(DocumentEvent e) {
Document doc = e.getDocument();
if (doc instanceof MirrorDocument) {
MirrorDocument md = (MirrorDocument) doc;
if (!md.isIgnoreUpdates()) {
try {
String text = e.getDocument().getText(e.getOffset(), e.getLength());
slaveDocument.setIgnoreUpdates(true);
slaveDocument.insertString(e.getOffset(), text, null);
} catch (BadLocationException ex) {
ex.printStackTrace();
} finally {
slaveDocument.setIgnoreUpdates(false);
}
}
}
}
@Override
public void removeUpdate(DocumentEvent e) {
Document doc = e.getDocument();
if (doc instanceof MirrorDocument) {
MirrorDocument md = (MirrorDocument) doc;
if (!md.isIgnoreUpdates()) {
try {
slaveDocument.setIgnoreUpdates(true);
slaveDocument.remove(e.getOffset(), e.getLength());
} catch (BadLocationException ex) {
ex.printStackTrace();
} finally {
slaveDocument.setIgnoreUpdates(false);
}
}
}
}
@Override
public void changedUpdate(DocumentEvent e) {
}
}
}
，pointList += point
是pointList个实例。您只能将另一个iterable添加到iterable中。
您可以使用以下方法修复它：
list或
point在您的情况下，您无需将Point3D分配给pointList += [point]
。您也不需要将变量绑定到新点。您可以将其直接添加到列表中，如下所示：
pointList.append(point)
答案 1 :(得分：3)
对list -
pointList += newPoint
类似于调用pointList.extend(newPoint)，在这种情况下，newPoint必须是可迭代的，其元素将添加到pointList。
如果你想要的只是简单地将元素添加到列表中，你应该使用list.append()方法 -
pointList.append(newPoint)