小编146*_*ian的帖子

我有DataFrame专栏Sales.

如何根据Sales价值将其拆分为2 ？

首先DataFrame是数据,'Sales' < s第二个是'Sales' >= s

我有一个包含内部类的Class.我想发送值,等于顶级类,但"this"发送内部类的值.我能做什么？

package Controller;
public class MessageFrameListener{
private MessageFrame mf;
private User us;
private Contact cn;
private Timer timer;
private Running run;
private ListFrame lf;

public MessageFrameListener(ListFrame l_f, MessageFrame m_f, User u_s, Contact c_n, Running r_n){
    run = r_n;
    mf = m_f;
    us = u_s;
    cn = c_n;
    lf = l_f;
    m_f.addButtonListener(new SButtonListener());
    m_f.addWinListener(new FrameListener());

    timer = new Timer(500,new timerListener());
    timer.start();
}


public class FrameListener implements WindowListener{

    @Override
    public void windowClosing(WindowEvent e) {
        timer.stop();
        timer = null;
        mf.close();
        lf.removeMFL(this));
    }       
} …

在我的android程序中,我显示大数字.为了使它们易于阅读,我想格式化这些数字,而不是像1000000,而是像1 000 000.

哪种格式化这样的字符串最简单？

我想要乘以2个矩阵.我需要逐个元素地将它们相乘.它们的大小是100x100.但为什么这个功能工作得很慢？大约2-3分钟.

for i=1:size(volumes,1)
  for j =1:size(volumes,2)
      ys(i,j) = volumes(i,j)*prices(i,j)

  end
end

如何加快这个操作？

我正在尝试用list创建一个函数.它是排序和删除重复项.它排序很好,但不删除重复项.有什么问题？

void sort_del(List<double> slist){
        //here i sort slist
        //get sorted with duplicates

        List<double> rlist = new List<double>();
        int new_i=0;
        rlist.Add(slist[0]);
        for (i = 0; i < size; i++)
        {
            if (slist[i] != rlist[new_i])
            {
                rlist.Add(slist[i]);
                new_i++;
            }

        }

        slist = new List<double>(rlist);
        //here get without duplicates
    }

在android studio中,如果我将.xml drawable设置为背景,我会得到渲染问题,并且在运行app时 - 看不到背景.

例如,我无法将此xml设置为布局的背景.

<?xml version="1.0" encoding="utf-8"?>
<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
android:src="@drawable/bad" />

如果我添加,例如,

android:tileMode="repeat"

结果是一样的.我还在背景附近看到红色感叹号:

这是堆栈跟踪:

java.lang.NullPointerException
at android.graphics.Bitmap_Delegate.createBitmap(Bitmap_Delegate.java:614)
at android.graphics.Bitmap_Delegate.createBitmap(Bitmap_Delegate.java:122)
at android.graphics.Bitmap_Delegate.createBitmap(Bitmap_Delegate.java:104)
at com.android.layoutlib.bridge.impl.ResourceHelper.getDrawable(ResourceHelper.java:249)
at android.content.res.BridgeTypedArray.getDrawable(BridgeTypedArray.java:674)
at android.view.View.<init>(View.java:3730)
at android.view.ViewGroup.<init>(ViewGroup.java:491)
at android.widget.LinearLayout.<init>(LinearLayout.java:200)
at android.widget.LinearLayout.<init>(LinearLayout.java:196)
at android.widget.LinearLayout.<init>(LinearLayout.java:192)
at sun.reflect.GeneratedConstructorAccessor302.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
at android.view.LayoutInflater.createView(LayoutInflater.java:607)
at android.view.BridgeInflater.onCreateView(BridgeInflater.java:82)
at android.view.LayoutInflater.onCreateView(LayoutInflater.java:682)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:741)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:128)
at android.view.LayoutInflater.inflate(LayoutInflater.java:482)
at android.view.LayoutInflater.inflate(LayoutInflater.java:385)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:400)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:332)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderService$5.compute(RenderService.java:708)
at com.android.tools.idea.rendering.RenderService$5.compute(RenderService.java:697)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:932)
at com.android.tools.idea.rendering.RenderService.createRenderSession(RenderService.java:697)
at com.android.tools.idea.rendering.RenderService.render(RenderService.java:816)
at com.intellij.android.designer.designSurface.AndroidDesignerEditorPanel$6.run(AndroidDesignerEditorPanel.java:480)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:320)
at …

这是代码

for (j = 0; j < n_sign; j++)
{
    line = new List<double>();
    for (i = 0; i < n_vec; i++)
    {
        if (data_gap[i][j] != gap)
            line.Add(data_gap[i][j]);
        else
        {
            grad.Add(0);
            List<int> point = new List<int>();
            point.Add(i);
            point.Add(j);
            gaps.Add(point);
        }
    }

    List<double> mm = new List<double>();
    mm.Add(line.Min());
    mm.Add(line.Max());
    minmax.Add(mm);

    for (i = 0; i < n_vec; i++)
    {
        if (data_gap[i][j] == gap)
            data[i][j] = line[rand.Next(line.Count)];
    }
}

我无法理解,为什么在这个函数之后data_gap的值会改变为数据的值!data_gap已经以这种方式创建

data_gap = new List<List<double>>(data);

所以它似乎是一个独特的对象......

这是我的课

public class MessageFrameListener{
private MessageFrame mf;
private User us;
private Contact cn;

private Socket s;
private PrintStream ps;
private BufferedReader br;


public MessageFrameListener(MessageFrame m_f, User u_s, Contact c_n){
    mf = m_f;
    us = u_s;
    cn = c_n;
    m_f.addButtonListener(new SButtonListener());
}

public void init(){
    try {
        s = new Socket(InetAddress.getLocalHost(), 8072);
        PrintStream ps = new PrintStream(s.getOutputStream());
        BufferedReader br = new BufferedReader( new InputStreamReader(s.getInputStream()));
    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // …

我想申报一个大常数.但java显示错误,我的常量对于int来说太大了.但我想要长久不变.该怎么办？

 public static final long MAXMONEY = 1000000000000000000;

我正在尝试在Eclipse中使用Breakpoints,但是当我设置它们时 - 没有任何反应.真.例如在MVS中,当程序到达断点时,它会停止,我可以看到变量.

如何以相同的方式在Eclipse中使用断点？