import java.applet.Applet;
import java.awt.*;
import java.util.*;

public class coor extends Applet
{
	int cj,jug;
	int wid=600,hei=500,bai=50;
	double px[] = new double[100];
	double py[] = new double[100];
	int cn = 0;
	String coo;
	TextField tx;
	List L;
	Button del;
	Graphics g;
	Vector vPointx = new Vector();
	Vector vPointy = new Vector();
	Vector vCoorx = new Vector();
	Vector vCoory = new Vector();
	static int nPoint = 0;

	public void init()
	{
		Panel p1 = new Panel();
		Panel p2 = new Panel();
		tx = new TextField("",50);
		L = new List();

		jug = 0;
		del = new Button("全て削除");
		setBackground(Color.white);
		setLayout(new BorderLayout());
		p1.setLayout(new BorderLayout());
		p1.add("Center",tx);
		p1.add("South",L);
		p1.add("East",del);
		p2.setBackground(Color.white);
		CheckboxGroup cg = new CheckboxGroup();
		Checkbox c = new Checkbox("グラフなし",cg,true);
		c.setBackground(Color.white);
		p2.add(c);
		c = new Checkbox("直線で結ぶ",cg,false);
		c.setBackground(Color.white);
		p2.add(c);
		c = new Checkbox("曲線で結ぶ",cg,false);
		c.setBackground(Color.white);
		p2.add(c);
		c = new Checkbox("最小二乗法",cg,false);
		c.setBackground(Color.white);
		p2.add(c);
		c = new Checkbox("座標を通過する",cg,false);
		c.setBackground(Color.white);
		p2.add(c);
		p2.add(new Button("拡大"));
		p2.add(new Button("縮小"));
		add("South",p1);
		add("North",p2);
		g = getGraphics();
	}

	public void sort(int n)
	{
		int i,min;
		Integer ix1,ix2,iy1,iy2;
		
		for (i = 0;i < n-1;i++)
		{
			min = i;
			for (int j = i+1;j < n;j++)
			{
				ix1 = (Integer)vPointx.elementAt(min);
				ix2 = (Integer)vPointx.elementAt(j);
				if (ix1.intValue() > ix2.intValue())
					min = j;
			}
			if (min != i)
			{
				ix1 = (Integer)vPointx.elementAt(i);
				ix2 = (Integer)vPointx.elementAt(min);
				vPointx.setElementAt(ix2,i);
				vPointx.setElementAt(ix1,min);
				iy1 = (Integer)vPointy.elementAt(i);
				iy2 = (Integer)vPointy.elementAt(min);
				vPointy.setElementAt(iy2,i);
				vPointy.setElementAt(iy1,min);
			}
		}
	}

	public void paint(Graphics g)
	{
		int i,di,cnt;
		double x,y,dx,dy,ix,iy;
		String buf;
		cn = 0;
		g.translate(wid/2,hei/2);
		g.drawLine(-wid/2,0,wid/2,0);
		g.drawLine(0,hei/2,0,-hei/2);
		g.drawString("0",-10,15);
		g.drawString("x",wid/2-15,-10);
		g.drawString("y",10,-hei/2+40);

		for (i = -(int)wid/bai;i <= (int)wid/bai;i++)
		{
			if (i == 0)
				i++;
			di = i*bai;
			buf = String.valueOf(i);
			g.drawString(buf,di-10,15);
			g.drawString(buf,-15,-di+15);
			g.drawLine(di,-5,di,5);
			g.drawLine(-5,di,5,di);
		}
		cnt = vPointx.size();
		for (i = 0;i < cnt;i++)
		{
			drawCoor(i);
		}
		if (jug == 1)
		{
			double idx=0,idy=0;
			Integer intx,inty;
			
			sort(cnt);
			ix = iy = 0;
			for (int f = 0;f < cnt;f++)
			{
				intx = (Integer)vPointx.elementAt(f);
				inty = (Integer)vPointy.elementAt(f);
				ix = intx.doubleValue();
				iy = inty.doubleValue();
				if (f != 0)
					g.drawLine((int)idx,(int)idy,(int)ix,(int)iy);
				idx = ix;
				idy = iy;
			}
		}
		else if (jug == 2)
		{
			int s,t,np,mm;
			double c1,c2,hl,hr,xmin,xmax,idx,tk;
			double a2[] = new double[100];
			double a3[] = new double[100];
			double xa[] = new double[100];
			double xb[] = new double[100];
			double xc[] = new double[100];
			double xd[] = new double[100];
			double xs[] = new double[100];
			double xu[] = new double[100];
			Integer intx1,intx2,inty1,inty2;
			
			mm = 100;
			dx = dy = ix = iy = 0;
			sort(cnt);

			if (cnt > 2)
			{
				np = cnt-2;
				for (s = 1;s <= np;s++)
				{
					intx1 = (Integer)vPointx.elementAt(s);
					intx2 = (Integer)vPointx.elementAt(s-1);
					hl = intx1.doubleValue() - intx2.doubleValue();
					intx2 = (Integer)vPointx.elementAt(s+1);
					hr = intx2.doubleValue() - intx1.doubleValue();
					xa[s] = hl/(hl+hr);
					xb[s] = 1-xa[s];
					inty1 = (Integer)vPointy.elementAt(s+1);
					inty2 = (Integer)vPointy.elementAt(s);
					c1 = (inty1.doubleValue() - inty2.doubleValue())/hr;
					inty1 = (Integer)vPointy.elementAt(s-1);
					c2 = (inty2.doubleValue() - inty1.doubleValue())/hl;
					xc[s] = 6.0*((c1-c2)/(hl+hr));
					xd[s] = 2.0;
				}
				for (s = 1;s < np;s++)
				{
					xb[s] = xb[s]/xd[s];
					xc[s] = xc[s]/xd[s];
					xd[s+1] = xd[s+1]-xa[s+1]*xb[s];
					xc[s+1] = xc[s+1]-xa[s+1]*xc[s];
				}
				xs[np] = xc[np]/xd[np];
				for (s = np-1;s > 0;s--)
					xs[s] = xc[s]-xb[s]*xs[s+1];
				intx1 = (Integer)vPointx.elementAt(1);
				intx2 = (Integer)vPointx.elementAt(0);
				hl = intx1.doubleValue() - intx2.doubleValue();
				inty1 = (Integer)vPointy.elementAt(1);
				inty2 = (Integer)vPointy.elementAt(0);
				xu[0] = (inty1.doubleValue() - inty2.doubleValue())/hl - hl*xs[1]/6.0;
				for (s = 1;s <= np+1;s++)
				{
					intx1 = (Integer)vPointx.elementAt(s);
					intx2 = (Integer)vPointx.elementAt(s-1);
					hl = intx1.doubleValue() - intx2.doubleValue();
					xu[s] = xu[s-1]+hl*(xs[s-1]+xs[s])/2.0;
				}
				for (s = 1;s <= np+1;s++)
				{
					intx1 = (Integer)vPointx.elementAt(s);
					intx2 = (Integer)vPointx.elementAt(s-1);
					hl = intx1.doubleValue() - intx2.doubleValue();
					a3[s] = (xs[s]-xs[s-1])/(6.0*hl);
					a2[s] = xs[s-1]/2.0;
				}
				intx1 = (Integer)vPointx.elementAt(0);
				xmin = intx1.doubleValue();
				intx2 = (Integer)vPointx.elementAt(cnt-1);
				xmax = intx2.doubleValue();
				idx = (xmax-xmin)/mm;
				s = 1;
				for (t = 0;t <= mm;t++)
				{
					x = xmin+idx*t;
					intx1 = (Integer)vPointx.elementAt(s);
					if (x >= intx1.doubleValue())
						s++;
					intx1 = (Integer)vPointx.elementAt(s-1);
					tk = x - intx1.doubleValue();
					inty1 = (Integer)vPointy.elementAt(s-1);
					y = ((a3[s]*tk+a2[s])*tk+xu[s-1])*tk+inty1.doubleValue();
					ix = x;
					iy = y;
					if (t != 0)
					{
						g.drawLine((int)dx,(int)dy,(int)ix,(int)iy);
					}
					dx = ix;
					dy = iy;
				}
			}
		}
		else if (jug == 3 || jug == 4)
		{
			drawGraph();
		}
	}
	
	public void setGraph()
	{
		double x,y,dx,dy,ix,iy;
		Integer ibx,iby;
		int cnt = vPointx.size();

		vCoorx.removeAllElements();
		vCoory.removeAllElements();
		if (jug == 3)
		{
			int h,len;
			double m,sumx,sumy,sumx2,sumxy,bb,a,b;
			String cc,bua,bub;
			char bufa[] = new char[10];
			char bufb[] = new char[10];
			dx = dy = sumx = sumy = sumx2 = sumxy = 0;
			nPoint = 0;

			for (int iCnt = 0;iCnt < cnt;iCnt++)
			{
				ibx = (Integer)vPointx.elementAt(iCnt);
				iby = (Integer)vPointy.elementAt(iCnt);
				double dbx = ibx.doubleValue()/bai;
				double dby = iby.doubleValue()/bai;
				sumx += dbx;
				sumy += dby;
				sumx2 += dbx*dbx;
				sumxy += dbx*dby;
			}
			bb = cnt*sumx2-sumx*sumx;
			a = (cnt*sumxy-sumx*sumy)/bb;
			b = (sumx2*sumy-sumx*sumxy)/bb;
			for (m = -wid/bai;m <= wid/bai;m += 0.01)
			{
				x = m;
				y = a*m+b;
				if (y > 299)
					y = 299;
				else if (y <- 299)
					y = -299;
				x = x*bai;
				y = y*bai;
				if (m != -wid)
				{
					Integer intx = new Integer((int)x);
					Integer inty = new Integer((int)y);
					vCoorx.addElement(intx);
					vCoory.addElement(inty);
					nPoint++;
				}
				dx = x;
				dy = y;
			}
		}
		else if (jug == 4)
		{
			int s,t,u,imax,len;
			double aik,ee,h,m,pp,v,z;
			String cc;
			double bx[][] = new double[100][100];
			double by[] = new double[100];
			double nx[] = new double[100];
			char bufn[] = new char[10];
			char buft[] = new char[10];
			dx = dy = 0;
			nPoint = 0;

			if (cnt > 1)
			{
				for (s = 0;s < cnt;s++)
				{
					for (t = 0;t < cnt;t++)
					{
						u = cnt-t-1;
						ibx = (Integer)vPointx.elementAt(s);
						double dbx = ibx.doubleValue()/bai;
						bx[s][t] = Math.pow(dbx,u);
					}
					iby = (Integer)vPointy.elementAt(s);
					double dby = iby.doubleValue()/bai;
					by[s] = dby;
				}
				for (s = 0;s < cnt-1;s++)
				{
					h = Math.abs(bx[s][s]);
					imax = s;
					for (t = s+1;t < cnt;t++)
					{
						aik = Math.abs(bx[t][s]);
						if (aik > h)
						{
							h = aik;
							imax = t;
						}
					}
					if (h == 0.0)
						return;
					if (imax != s)
					{
						for (t = s;t < cnt;t++)
						{
							ee = bx[s][t];
							bx[s][t] = bx[imax][t];
							bx[imax][t] = ee;
						}
						ee = by[s];
						by[s] = by[imax];
						by[imax] = ee;
					}
					pp = bx[s][s];
					for (t = s;t < cnt;t++)
						bx[s][t] = bx[s][t]/pp;
					by[s] = by[s]/pp;
					for (t = s+1;t < cnt;t++)
					{
						v = bx[t][s];
						for (u = s;u < cnt;u++)
							bx[t][u] = bx[t][u]-v*bx[s][u];
						by[t] = by[t]-v*by[s];
					}
				}
				nx[cnt] = by[cnt]/bx[cnt][cnt];
				for (s = cnt-1;s >= 0;s--)
				{
					z = by[s];
					for (t = s+1;t < cnt;t++)
						z = z-bx[s][t]*nx[t];
					nx[s] = z;
				}
				for (m = -wid/bai;m <= wid/bai;m += 0.01)
				{
					x = m;
					y = 0.0;
					cc = "";
					for (s = 0;s < cnt;s++)
					{
						t = cnt-s-1;
						y += nx[s]*Math.pow(m,t);
					}
					if (y > 299)
						y = 299;
					else if (y <- 299)
						y = -299;
					x = x*bai;
					y = y*bai;
					if (m != -wid)
					{
						Integer intx = new Integer((int)x);
						Integer inty = new Integer((int)y);
						vCoorx.addElement(intx);
						vCoory.addElement(inty);
						nPoint++;
					}
					dx = x;
					dy = y;
				}
			}
		}
	}

	public boolean action(Event e,Object o)
	{
		if (e.target instanceof Checkbox)
		{
			Checkbox c = (Checkbox)e.target;
			if ("グラフなし".equals(c.getLabel()))
			{
				jug = 0;
			}
			else if ("直線で結ぶ".equals(c.getLabel()))
			{
				jug = 1;
			}
			else if ("曲線で結ぶ".equals(c.getLabel()))
			{
				jug = 2;
			}
			else if ("最小二乗法".equals(c.getLabel()))
			{
				jug = 3;
				setGraph();
			}
			else if ("座標を通過する".equals(c.getLabel()))
			{
				jug = 4;
				setGraph();
			}
		}
		else if (e.target instanceof TextField)
		{
			coo = (String)o;
			cj = 0;
			Coordinates(coo);
			coo = "( "+coo+")";
			L.addItem(coo);
			if (cj != -1)
			{
				tx.setText("");
				coo = "";
			}
		}
		else if (e.target instanceof Button)
		{
			Button b = (Button)e.target;
			if ("全て削除".equals(b.getLabel()))
			{
				L.clear();
				tx.setText("");
				vPointx.removeAllElements();
				vPointy.removeAllElements();
				vCoorx.removeAllElements();
				vCoory.removeAllElements();
			}
			else if ("拡大".equals(b.getLabel()))
			{
				if (bai < 100)
				{
					bai += 10;
					vPointx.removeAllElements();
					vPointy.removeAllElements();
					vCoorx.removeAllElements();
					vCoory.removeAllElements();
					for (int iCnt = 0;iCnt < L.getItemCount();iCnt++)
					{
						String str = L.getItem(iCnt);
						str = str.substring(1,str.length()-1);
						Coordinates(str);
						setGraph();
					}
				}
				else
					return true;
			}
			else if ("縮小".equals(b.getLabel()))
			{
				if (bai > 20)
				{
					bai -= 10;
					vPointx.removeAllElements();
					vPointy.removeAllElements();
					vCoorx.removeAllElements();
					vCoory.removeAllElements();
					for (int iCnt = 0;iCnt < L.getItemCount();iCnt++)
					{
						String str = L.getItem(iCnt);
						str = str.substring(1,str.length()-1);
						Coordinates(str);
						setGraph();
					}
				}
				else
					return true;
			}
		}
		repaint();
		return true;
	}

	public boolean mouseUp(Event e,int x,int y)
	{
		double x1,y1;
		String dot = "";
		coo = "";
		if (y < 35 || y > hei-80)
			return true;
		x1 = x-wid/2;
		y1 = y-hei/2;
		x1 = x1/bai;
		y1 = -y1/bai;
		dot = Double.toString(x1);
		if (x1 > 0.0)
			dot = " "+dot;
		if (dot.length() > 5)
			coo = dot.substring(0,5);
		else
			coo = dot;
		coo = coo+',';
		dot = "";
		dot = Double.toString(y1);
		if (y1 > 0.0)
			dot = " "+dot;
		if (dot.length() > 5)
			dot = dot.substring(0,5);
		coo = coo+dot;
		Coordinates(coo);
		coo = "( "+coo+")";
		L.addItem(coo);
		if (jug == 3 || jug == 4)
			setGraph();
		repaint();
		return true;
	}

	public void cerr()
	{
		cj = -1;
	}

	public void Coordinates(String coo)
	{
		coo = coo+' ';
		int i,len;
		double x=0,y=0,x1,x2;
		char a;
		g = getGraphics();
		g.translate(wid/2,hei/2);
		len = coo.length();
		int b = 0;
		int c = -1;

		for (i = 0;i < len;i++)
		{
			a = coo.charAt(i);
			if (a == '-')
			{
				c = -c;
				if (i !=0 && cj == i)
				{
					cerr();
					showStatus("正しく入力してください。");
					return;
				}
			}
			else if (a >= '0' && a <= '9')
			{
				x1 = a-'0';
				cj = i+1;
				while ((a = coo.charAt(++i)) >= '0' && a <= '9')
					x1 = 10*x1+(a-'0');
				if (a == '.')
				{
					x2 = 1.0;
					while ((a = coo.charAt(++i)) >= '0' && a <= '9')
					{
						x2 = x2/10.0;
						x1 = x1+x2*(a-'0');
					}
				}
				a = coo.charAt(--i);
				if (c == 1)
					x1 = -x1;
				if (b == 0)
					x = x1;
				else
					y = x1;
			}
			else if (a == ',')
			{
				if (b == 1)
				{
					cerr();
					showStatus("x , y の形式で入力してください。");
					return;
				}
				b = 1;
				c = -1;
				x1 = 0;
			}
			else if (a == ' ')
				cj++;
			else if (a == '+')
			{
				if (i == 0) ;
				else if (cj == i)
				{
					cerr();
					showStatus("正しく入力してください。");
					return;
				}
			}
			else
			{
				cerr();
				showStatus("正しく入力してください。");
				return;
			}
		}
		if (b == 0)
		{
			cerr();
			showStatus("x , y の形式で入力してください。");
			return;
		}
		px[cn] = x;
		py[cn] = y;
		cn++;
		x = x*bai;
		y = -y*bai;
		Integer ix = new Integer((int)x);
		Integer iy = new Integer((int)y);
		vPointx.addElement(ix);
		vPointy.addElement(iy);
	}
	
	public void drawCoor(int i)
	{
		double x,y;
		Integer ix,iy;
		String strCoor;
		ix = (Integer)vPointx.elementAt(i);
		iy = (Integer)vPointy.elementAt(i);
		g = getGraphics();
		g.translate(wid/2,hei/2);
		g.fillOval(ix.intValue()-1,iy.intValue()-1,3,3);
		x = ix.doubleValue();
		y = -iy.doubleValue();
		x = x/50;
		y = y/50;
		strCoor = L.getItem(i);
		g.drawString(strCoor,ix.intValue()+2,iy.intValue()+15);
	}

	public void drawGraph()
	{
		int xPoint[] = new int[nPoint];
		int yPoint[] = new int[nPoint];
		Integer ix,iy;
		
		for (int ipos = 0;ipos < nPoint;ipos++)
		{
			ix = (Integer)vCoorx.elementAt(ipos);
			iy = (Integer)vCoory.elementAt(ipos);
			xPoint[ipos] = ix.intValue();
			yPoint[ipos] = iy.intValue();
		}
		g = getGraphics();
		g.translate(wid/2,hei/2);
		g.drawPolyline(xPoint,yPoint,nPoint);
	}
}