Rafico
04 de Junio del 2008

Cuando compilo muestra un warning y cuando lo ejecuto me muestra el mensaje "Exception in thread "main" java.lang.NoSuchMethodError: main", el codigo es el siguiente:

/* File: Twophase.java */
/* Copyright (C) 1997 K. Ikeda */

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


class RN {
int n;
int d;

RN() {n=0; d=1;}
RN(int n) {this.n=n; this.d=1;}
RN(int n, int d) {this.n=n; this.d=d; reduce();}
RN(String s) {
int k = s.indexOf(\'/\');
if (k>0) {
d = Integer.valueOf(s.substring(k+1)).intValue();
s = s.substring(0,k);
} else
d = 1;
n = Integer.valueOf(s).intValue();
reduce();
}

int euclid(int a, int b) {
int q,r;

if (a < 0) a = -a;
if (b < 0) b = -b;
if (b == 0)
if (a==0)
return -1;
else
return a;
for (;;) {
q = a / b;
r = a % b;
if (r==0)
break;
a = b;
b = r;
}
return b;
}

boolean reduce() {
int c;

if ((c = euclid(n,d))<0)
return false;
if (d<0)
c *= -1;
n /= c;
d /= c;
return true;
}

void set(int n) {this.n=n; this.d=1;}
void set(int n, int d) {this.n=n; this.d=d;}
void set(RN a) {n=a.n; d=a.d;}

void mul(RN a) {
a.reduce();
RN aa = new RN(n,a.d);
RN bb = new RN(a.n,d);
aa.reduce();
bb.reduce();
n = aa.n * bb.n;
d = aa.d * bb.d;
}

void div(RN a) {
a.reduce();
RN aa = new RN(n, a.n);
RN bb = new RN(a.d, d);
aa.reduce();
bb.reduce();
n = aa.n * bb.n;
d = aa.d * bb.d;
}

void inv() {int x; x = n; n = d; d = x; reduce();}

boolean plus(RN a) {
int c,x,y;

c = euclid(d, a.d);
if (c < 0)
return false;
if ((x = a.d/c*n + d/c*a.n)==0) {
x = 0;
y = 1;
} else
y = d/c*a.d;
n = x;
d = y;
this.reduce();
return true;
}

boolean minus(RN a) {
int c,x,y;

c = euclid(d, a.d);
if (c < 0)
return false;
if ((x = a.d/c*n - d/c*a.n)==0) {
x = 0;
y = 1;
} else
y = d/c*a.d;
n = x;
d = y;
this.reduce();
return true;
}

boolean gt(RN a) {RN c=new RN(n,d); c.minus(a); return c.n>0;}
boolean ge(RN a) {RN c=new RN(n,d); c.minus(a); return c.n>=0;}
boolean eq(RN a) {RN c=new RN(n,d); c.minus(a); return c.n==0;}
boolean le(RN a) {RN c=new RN(n,d); c.minus(a); return c.n<=0;}
boolean lt(RN a) {RN c=new RN(n,d); c.minus(a); return c.n<0;}
}

public class Twophase extends Applet {
int m,n,r,s;
int step,cycle,phase;
RN[][] a = new RN[10][20];
int[] base = new int[10];
String message = "";

void Print(Graphics g, FontMetrics fm, int x, int y, String s) {
int w = fm.stringWidth(s);
int h = fm.getHeight();
g.drawString(s,x-w/2,y-h/2+fm.getAscent());
}

void Print(Graphics g, FontMetrics fm, int x, int y, int n) {
Print(g,fm,x,y,""+n);
}

void Print(Graphics g, FontMetrics fm, int x, int y, RN rn) {
int wn, wd, h = fm.getHeight();
int sign;

if (rn.n<0)
sign = -1;
else
sign = 1;
if (rn.d == 1) {
Print(g,fm,x,y,sign*rn.n);
wd = fm.stringWidth(""+(sign*rn.n));
} else {
Print(g,fm,x,y-h/2-2,sign*rn.n);
Print(g,fm,x,y+h/2+2,rn.d);
wn = fm.stringWidth(""+sign*rn.n);
wd = fm.stringWidth(""+rn.d);
if (wn>wd)
wd = wn;
g.drawLine(x-wd/2,y-1,x+wd/2,y-1);
}
if (sign<0) {
wn = wd/2+fm.stringWidth("-")+2;
wd = fm.getHeight();
g.drawString("-",x-wn,y-wd/2+fm.getAscent());
}
}

void input_data() {
m = Integer.parseInt(getParameter("m"));
n = Integer.parseInt(getParameter("n"));
String sdat = getParameter("data");
StringTokenizer st = new StringTokenizer(sdat,",");
for (int i = 0; i<=m; i++) {
for (int j=0; j<=n; j++)
a[i][j] = new RN(st.nextToken());
base[i] = n+i;
}
for (int j=0; j<=n; j++) {
RN t = new RN();

for (int i=0; i<m; i++)
t.minus(a[i][j]);
a[m+1][j] = t;
}
}

boolean step1() { /* search pivot s of (r, s) */
RN c = new RN();

s = 0; r = -1;
c.set(a[m+2-phase][s]);
for (int j=1; j<n; j++)
if (c.gt(a[m+2-phase][j])) {
s = j;
c.set(a[m+2-phase][s]);
}
if (c.n>=0) {
s = -1;
return true;
} else
return false;
}

boolean step2() { /* search pivot r of (r, s) */
RN t = new RN();
RN c = new RN();

for (int i=0; i<m; i++) {
if (a[i][s].n<=0)
continue;
t.set(a[i][n]);
t.div(a[i][s]);
if (r<0 || t.lt(c)) {
r = i;
c.set(t);
}
}
if (r<0)
return true;
else
return false;
}

void step3() { /* pivot operation 1 */
RN c = new RN();

base[r] = s;
c.set(a[r][s]);
for (int j=0; j<=n; j++)
a[r][j].div(c);
}

void step4() {
RN c = new RN();
RN t = new RN();

for (int i=0; i<=m+2-phase; i++) {
if (i == r)
continue;
c.set(a[i][s]);
for (int j=0; j<=n; j++) {
t.set(c);
t.mul(a[r][j]);
a[i][j].minus(t);
}
}
r = s = -1;
}

public void init() {
input_data();
step = cycle = 0;
phase = 1;
s = r = -1;
message = "click here.";
setBackground(Color.white);
}

void select_color(Graphics g, int i, int j) {
Color c;

if ((step==1&&i==m+2-phase&&j==s)||(step!=1&&i==r&&j==s))
c = Color.red;
else if ((step==1&&i==m+2-phase&&j<n&&a[i][j].n<0)||
(step==2&&(j==s||j==n)&&i<m&&a[i][s].n>0)||
(step==3&&(i==r||j==s)))
c = Color.blue;
else
c = Color.black;
g.setColor(c);
}

public void paint(Graphics g) {
int w,h;
int x,y;

FontMetrics fm = g.getFontMetrics();
w = fm.stringWidth("012345")+10;
h = fm.getHeight()*2+4;

x = 25 + w/2;
y = 25 + h/2;
g.setColor(getBackground());
g.fillRect(25,25-h/2,10*w,(h-4)/2+1);
g.fillRect(x-w/2,y-h/2,(n+2)*w+1,h+1);
g.setColor(Color.black);
g.drawString("Phase "+phase+" Cycle "+cycle+": "+message,
25,25-h/2+fm.getAscent());
Print(g,fm,x,y,"basis");
for (int j=0; j<n; j++) {
x += w;
Print(g,fm,x,y,"x"+(j+1));
}
x += w;
Print(g,fm,x,y,"const");
for (int i=0; i<=m+2-phase; i++) {
x = 25 + w/2;
y += h;
g.setColor(getBackground());
g.fillRect(x-w/2,y-h/2,(n+2)*w+1,h+1);
g.setColor(Color.black);
if (i==m)
Print(g,fm,x,y,"-z");
else if (i==m+1)
Print(g,fm,x,y,"-w");
else
Print(g,fm,x,y,"x"+(base[i]+1));
for (int j=0; j<=n; j++) {
select_color(g,i,j);
x += w;
Print(g,fm,x,y,a[i][j]);
}
}
}

public void update(Graphics g) {
paint(g);
}

public boolean mouseDown(Event ev, int x, int y)
{
boolean isOptimal = false;
boolean isUnbounded = false;

switch (step) {
case 0:
if (isOptimal=step1()) {
if (phase==2)
message="Optimal";
else if (a[m+1][n].n==0) {
phase = 2;
step--;
isOptimal=false;
message="Go to Phase II";
} else
message="No feasible solutions.";
} else
message = "Select x"+(s+1)+" to enter the basis.";
break;
case 1:
if (isUnbounded=step2())
message = "Unbounded";
else
message = "Select x"+(base[r]+1)+" to leave the basis.";
break;
case 2:
step3();
message = "Replace the simplex tableau.";
break;
case 3:
step4();
message = "Repeat the cycle.";
cycle++;
break;
case 4:
init();
message = "Click here";
repaint();
return true;
default:
break;
}
step++;
repaint();
step %= 4;
if (isOptimal||isUnbounded)
step = 4;
return true;
}
}

peketa
04 de Junio del 2008

Yo tengo ese mismo problema con todos los programas que quiero ejecutar. soy novata y llevo semanas con esto. ¡POR FAVOR AYUDA!