Thread: Designing RLC Circuit using Java Applet

The applet i am creating is a RLC circuit that have adjustable inputs with a graph as the output. When i am compiling the code i get the following errors: "cannot find symbol - class metrix" and "cannot find symbol - class curseurv." I am using BlueJ to write my code...i used some code i found online to construct the applet. Here is the link to what it is "suppose to look like:" Bouchon

Here is my code, I hope someone can help...THANKS!

import java.applet.Applet; 
import java.awt.*;   
public class rlc extends Applet 
{     
 String format(double r, int n, int d)     
{         
d++;      
String s = Double.toString(r);      
if((s.indexOf(".") != -1) & (s.length() > d + 2))            
s = s.substring(0, s.indexOf(".") + d);       
else      
if(s.length() > n)           
s = s.substring(0, n);      
return s;     
}     
void cadre3D(int x, int y, int f, int h)    
 {       
Color blanc = new Color(230, 230, 230);        
Color gris = new Color(130, 130, 130);         
g.setColor(gris);      
g.drawLine(x, y, f, y);    
g.drawLine(x, y + 1, f - 1, y + 1);         
g.drawLine(x, y, x, h);         
g.drawLine(x + 1, y, x + 1, h - 1);         
g.setColor(blanc);         
g.drawLine(x, h, f, h);        
g.drawLine(f, y + 1, f, h);        
g.drawLine(x + 1, h - 1, f, h - 1);        
g.drawLine(f - 1, y + 2, f - 1, h);     
}      
void separe(int y)     
{         
g.setColor(Color.white);         
g.drawLine(1, y + 1, 580, y + 1);         g.setColor(Color.gray);         
g.drawLine(1, y, 580, y);    
}      
public void paint(Graphics h)     
{         
double yi = 0.0D;         
double t = 0.0D;         
double t1 = 0.0D;         
double phi = 0.0D;         
double A = 1.0D;         
double ui = 0.0D;         
int k = 1;         
g.setColor(Color.lightGray);         
g.fillRect(0, 0, size().width, size().height);         separe(34);         
schema();         
generateur();         
scope();         
double w = 6.2831853071795862D * f;        
double T = 1.0D / (2D * f);        
double pas = tmax / 200D;         
double ec = 10D / tmax;        
if(mode == 1)         
{             
double a = R - L * R * C * w * w;             
double b = r * R * C * w;             
n = new comp(a, b);             
a += r;             
b += L * w;             
d = new comp(a, b);         
} else         
{             
double a = 0.0D;             
double b = R * C * w;             
n = new comp(a, b);             
a = 1.0D - L * C * w * w;             
b = (R + r) * C * w;             
d = new comp(a, b);         
}         
H = comp.quotient(n, d);         
A = comp.norme(H);         
phi = comp.phase(H);         
g.setColor(Color.green);         
double zi = A * (E * Math.sin(phi)) * G[indez];         
if(zi > 5D)             
zi = 5D;         
if(zi < -5D)             
zi = -5D;         
while(t < tmax)          
{             
t += pas;             
double yf = E * Math.sin(w * t) * G[indey];             
if(yf > 5D)                 
yf = 5D;             
if(yf < -5D)                 
yf = -5D;             
double zf = A * (E * Math.sin(w * t + phi)) * G[indez];             if(zf > 5D)                 
zf = 5D;             
if(zf < -5D)                 
zf = -5D;             
droite(ec * (t - pas), yi, ec * t, yf);             
droite(ec * (t - pas), zi, ec * t, zf);             
yi = yf;            
zi = zf;         
}         
g.setColor(Color.black);         
g.drawRect(260, 50, 290, 290);         
h.drawImage(imag, 0, 0, Color.white, this);         showStatus("Vishal Patel 5-2009");     
}      
public boolean mouseUp(Event evt, int x, int y)     
{         
if(actifa && y >= curV.inf && y <= curV.sup)         
{             
curV.ybou = y;             
actifa = false;             
repaint();         
}         
if(actifb && y >= curF.inf && y <= curF.sup)         
{             
curF.ybou = y;             
actifb = false;             
repaint();         
}         
if(!f1)         
{             
f1 = true;             
repaint();         
}         
if(!f2)         
{             
f2 = true;             
repaint();         
}         
if(!f3)         
{             
f3 = true;             
repaint();         
}         
if(!f4)         
{             
f4 = true;             
repaint();         
}         
return true;     
}      
public void destroy()     
{         
imag.flush();     
}      
void droite(double xi, double yi, double xf, double yf)     
{         
xei = 260 + (int)((288D * xi) / 10D);         
yei = 50 + (int)((290D * (5D - yi)) / 10D);         
xef = 260 + (int)((288D * xf) / 10D);         
yef = 50 + (int)((290D * (5D - yf)) / 10D);         
g.drawLine(xei, yei, xef, yef);     
}      
public void update(Graphics h)     
{         
paint(h);     
}      
void schema()     
{         
int X[] = new int[45];         
int Y[] = new int[45];         
if(mode == 1)         
{             
int i = 0;             
do             
{                 
X[i] = Xl[i] + 50;                 
Y[i] = Yl[i] + 60;             
} while(++i < 41);             
g.setColor(Color.black);             
g.drawPolygon(Y, X, 41);             g.setColor(Color.lightGray);             
g.drawLine(60, 66, 118, 66);             g.setColor(Color.black);             
g.drawLine(25, 160, 210, 160);             
g.drawLine(60, 65, 60, 105);             
g.drawLine(118, 65, 118, 105);             
g.drawLine(60, 105, 118, 105);             
g.fillRect(82, 90, 16, 30);             
g.drawLine(25, 80, 60, 80);             
g.drawLine(118, 80, 210, 80);             
g.drawLine(170, 80, 170, 160);             
g.drawString("R = 1 k" + s1, 190, 125);             g.setColor(Color.lightGray);             
g.fillRect(87, 90, 6, 30);             g.setColor(Color.yellow);             
g.fillRect(160, 95, 20, 50);             g.setColor(Color.black);             
g.drawRect(160, 95, 20, 50);             
g.drawString("r = " + format(r, 4, 1) + " " + s1, 130, 55);         
} else         
{             
int i = 0;             
do             
{                 
X[i] = Xl[i] + 50;                 
Y[i] = Yl[i] + 40;            
} while(++i < 41);             
g.setColor(Color.black);             
g.drawPolygon(Y, X, 41);             g.setColor(Color.lightGray);             
g.drawLine(40, 66, 98, 66);             g.setColor(Color.black);             
g.drawLine(25, 160, 210, 160);             
g.drawLine(25, 65, 40, 65);             
g.drawLine(98, 65, 215, 65);             
g.fillRect(110, 50, 16, 30);             
g.drawLine(160, 65, 160, 160);             g.setColor(Color.lightGray);             
g.fillRect(115, 50, 6, 30);             g.setColor(Color.yellow);             
g.fillRect(150, 90, 20, 50);             g.setColor(Color.black);             
g.drawRect(150, 90, 20, 50);             
g.drawString("R = 1 k" + s1, 180, 115);             
g.drawString("r = " + format(r, 4, 1) + " " + s1, 35, 100);         }     
}      
void generateur()     
{         
curV.dessine();         
curF.dessine();         
E = curV.val;         
f = curF.val;         
bal = (int)Math.round(2D * f) - 1;         
f = Math.pow(10D, f);         
double fre;         
if(f > 10000D)         
{             
fre = f / 1000D;             
freq.lab = "kHz";         
} else         
{             
fre = f;             
freq.lab = "Hz";         
}         
volt1.draw(E);         
freq.draw(fre);         
cadre3D(20, 180, 230, 390);     
}      
public boolean action(Event event, Object obj)     
{         
if(event.target == chx1)         
{             
L = Li[chx1.getSelectedIndex()];            
r = ri[chx1.getSelectedIndex()];         
} else         
if(event.target == chx2)             
C = Ci[chx2.getSelectedIndex()];         
else         
if(event.target == cb1)             
mode = 1;         
else         
if(event.target == cb2)             
mode = 2;         else             
return super.action(event, obj);         
repaint();         
return true;     
}      
void scope()     
{        
 g.setFont(font);         
g.setColor(vert);         
g.fillRect(260, 50, 290, 290);         g.setColor(Color.lightGray);         
droite(0.0D, 0.0D, 10D, 0.0D);         
int i = 0;         
do             
droite(i, -0.20000000000000001D,  i,0.20000000000000001D);         
while(++i < 10);         
droite(5D, -5D, 5D, 5D);         
i = -5;         
do             
droite(4.9000000000000004D, i, 5.0999999999999996D, i);         while(++i < 6);         
g.setColor(Color.gray);         
g.fill3DRect(370, 350, 15, 15, f1);         
g.fill3DRect(370, 370, 15, 15, f2);         
g.fill3DRect(260, 350, 15, 15, f3);         
g.fill3DRect(260, 370, 15, 15, f4);         g.setColor(Color.white);         
if(f1)             
g.drawString("+", 374, 362);         
else             
g.drawString("+", 373, 361);         
if(f2)            
g.drawString("-", 374, 382);         
else             
g.drawString("-", 373, 381);         
if(f3)             
g.drawString("+", 264, 362);         
else             
g.drawString("+", 263, 361);         
if(f4)             
g.drawString("-", 264, 382);         
else             
g.drawString("-", 263, 381);         
g.setColor(Color.blue);         
g.drawString("Gain Out", 390, 360);         
g.drawString("Gain Inp", 280, 360);         
g.drawString(sg[indez] + " V/cm", 390, 380);         g.drawString(sg[indey] + " V/cm", 280, 380);         switch(bal)         
{         
case 2: // '\002'         
case 3: // '\003'             
tmax = 0.050000000000000003D;             
s = "5 ms/cm";             
break;          
case 4: // '\004'             
tmax = 0.01D;             
s = "1 ms/cm";             
break;          
case 5: // '\005'             
tmax = 0.0050000000000000001D;             
s = "0.5 ms/cm";             
break;          
case 6: // '\006'             
tmax = 0.001D;             
s = "100 \265s/cm";             
break;          
case 7: // '\007'             
tmax = 0.00050000000000000001D;             
s = "50 \265s/cm";             
break;          
case 8: // '\b'             
tmax = 0.0001D;             
s = "10 \265s/cm";             
break;          
case 9: // '\t'             
tmax = 5.0000000000000002E-005D;             
s = "5 \265s/cm";             
break;          
case 10: // '\n'             
tmax = 1.0000000000000001E-005D;             
s = "1 \265s/cm";             
break;          
case 11: // '\013'             
tmax = 5.0000000000000004E-006D;             
s = "0.5 \265s/cm";             
break;         
}         
g.drawString("Time Division :", 470, 360);         
g.drawString(s, 470, 380);         
g.setColor(Color.black);         
g.drawRect(260, 50, 290, 290);     
}      
public boolean mouseDown(Event evt, int x, int y)     
{         
Rectangle test = new Rectangle(curV.X[2], curV.Y[0], 18, 6);         
if(test.inside(x, y))         
{             
actifa = true;             
actifb = false;         
}         
test = new Rectangle(curF.X[2], curF.Y[0], 18, 6);         if(test.inside(x, y))         
{             
actifb = true;             
actifa = false;         
}         
if(r1.inside(x, y))         
{             
f1 = false;             
actifb = false;             
actifa = false;             
indez++;             
if(indez > 6)                 
indez = 6;         
}         
if(r2.inside(x, y))         
{             
f2 = false;             
actifb = false;             
actifa = false;             
indez--;             
if(indez < 0)                 
indez = 0;         
}         
if(r3.inside(x, y))         
{             
f3 = false;             
actifb = false;             
actifa = false;             
indey++;             
if(indey > 8)                 
indey = 8;        
 }         
if(r4.inside(x, y))         
{             
f4 = false;             
actifb = false;             
actifa = false;             
indey--;             
if(indey < 0)                 
indey = 0;         
}         
repaint();         
return true;     
}      
public void init()     
{         
setFont(font);         
imag = createImage(size().width, size().height);         
g = imag.getGraphics();         setBackground(Color.lightGray);         
setLayout(fl);         
add(cb1);         
add(cb2);         
chx1.addItem("100 mH");         
chx1.addItem("1 H");         
chx1.addItem("10 mH");         
chx1.addItem("1 mH");         
chx2.addItem("10 nF");         
chx2.addItem("1 nF");         
chx2.addItem("100 nF");         
chx2.addItem("1 \265F");         
add(lb1);         
add(chx1);         
add(lb2);         
add(chx2);         
volt1 = new metrix(g, 35, 190, 5, "V", Color.green, 5D, 0.0D);         
freq = new metrix(g, 135, 190, 5, "Hz", Color.red, 0.0D);         curV = new curseurv(g, 70, 230, 370, 0.0D, 5D, 2.5D, Color.green);         
curF = new curseurv(g, 170, 230, 370, 1.6499999999999999D, 5.8499999999999996D, 3D, Color.red);         
Xo[0] = 150;         
Xo[1] = 210;         
Xo[2] = Xo[0];         
Yo[0] = 125;         
Yo[1] = 155;         
Yo[2] = 185;     
}      
public boolean mouseDrag(Event evt, int x, int y)     
{         
if(actifa && y >= curV.inf && y <= curV.sup)         
{             
curV.ybou = y;             
repaint();         
}         
if(actifb && y >= curF.inf && y <= curF.sup)         
{             
curF.ybou = y;             
repaint();         
}         
return true;     
}      
public rlc()     
{         
fl = new FlowLayout(1, 10, 3);         
chx1 = new Choice();         
chx2 = new Choice();         
lb1 = new Label("L=", 2);         
lb2 = new Label("C=", 2);         
bg1 = new CheckboxGroup();         
cb1 = new Checkbox("Parallel Circuit", bg1, true);         
cb2 = new Checkbox("Series Circuit", bg1, false);         
r1 = new Rectangle(370, 350, 15, 15);         
r2 = new Rectangle(370, 370, 15, 15);         
r3 = new Rectangle(260, 350, 15, 15);         
r4 = new Rectangle(260, 370, 15, 15);         
vert = new Color(0, 128, 0);         
fontp = new Font("TimesRoman", 0, 11);         
font = new Font("Courier", 0, 11);         
s1 = "" + '\u03A9';         
f1 = true;         
f2 = true;         
f3 = true;         
f4 = true;         
L = 0.10000000000000001D;         
r = 10D;         
C = 1E-008D;         
R = 1000D;         
Xo = new int[5];         
Yo = new int[5];         
mode = 1;         
indez = 3;         
indey = 3;     
}      
FlowLayout fl;     
Choice chx1;     
Choice chx2;     
Label lb1;     
Label lb2;     
CheckboxGroup bg1;     
Checkbox cb1;     
Checkbox cb2;     
Rectangle r1;     
Rectangle r2;     
Rectangle r3;     
Rectangle r4;     
metrix volt1;     
metrix freq;     
curseurv curV;     
curseurv curF;     
Color vert;     
Image imag;     
Graphics g;     
Font fontp;     
Font font;     
String s;     
String s1;     
boolean actifa;     
boolean actifb;     
boolean f1;     
boolean f2;     
boolean f3;     
boolean f4;     
final double PI = 3.1415926535897931D;     
double L;     
double Li[] = {         
0.10000000000000001D, 1.0D, 0.01D, 0.001D     
};     
double r;     
double ri[] = {         
10D, 80D, 3D, 0.5D     
};     
double C;     
double Ci[] = {         
1E-008D, 1.0000000000000001E-009D, 9.9999999999999995E-008D, 9.9999999999999995E-007D     };     
double E;     
double v;     
double vs;     
double f;     
double tmax;     
double R;     
double G[] = {         
0.10000000000000001D, 0.20000000000000001D, 0.5D, 1.0D, 2D, 5D, 10D, 20D, 50D     
};     
String sg[] = {         
"10", "5.0", "2.0", "1.0", "0.5", "0.2", "0.1", "0.05", "0.02"     
};     
int Yl[] = {         
0, 1, 4, 7, 12, 15, 19, 20, 19, 16,          
12, 12, 13, 15, 19, 24, 28, 31, 33, 32,          
29, 25, 25, 26, 28, 33, 37, 41, 44, 45,          
44, 41, 38, 37, 38, 41, 45, 49, 53, 56,          
58     
};     
int Xl[] = {         
16, 10, 4, 0, 0, 4, 10, 16, 22, 29,          
22, 16, 10, 4, 0, 0, 4, 10, 16, 22,          
29, 22, 16, 10, 4, 0, 0, 4, 10, 16,          
22, 29, 22, 16, 10, 4, 0, 0, 4, 8,          
16     
};     
int Xo[];     
int Yo[];     
int xei;     
int yei;     
int xef;     
int yef;     
int mode;     
int indez;     
int indey;     
int bal;     
int forme;     
comp H;     
comp n;     
comp d;     
int Xs;     
int Ys;     
FontMetrics fm; 
}

First of all wanted to say thanks for the help...i kind of figured that was it...i was trying to use the source from an online applet and just modify it, but when i compiled i got those errors. Is there anyway you can help...i believe i decompiled the source from the first link in my original post...if anyone can help it would be great. I need an applet similar to the links above.

Thank You!

Hi syxxpac316.

You can't compile without the classes that's missing. Its better to search again in the net from where you got this code for the missing class.
All the best.

thats exactly where i got the .class file from...its the first time i have ever decompiled a class...can i get the other classes from the site with bouchon.class? Or do i use the decompiler to obtain that?...i was trying to use that applet and modify it but could not get it work because of the missing classes.