rule 30 finite automaton

Hello all,

This is my finite automaton rule 30. Some reason it is not printing out the correct pattern and I can not figure it out

public class CA_1D2S
{
public CA_1D2S() {
try {
jbInit();
} catch (Exception ex) {
ex.printStackTrace();
}
}

byte[][] DOUBLE_BUFFER;
int CurRow = 0;
int nxtRow = 1;
int RowSize = 181;
int cellStates = 2;
byte[] rules = {0,1,1,1,1,0,0,0};


public CA_1D2S(int RowSize)
{
DOUBLE_BUFFER = new byte[2][RowSize];
Initialize();
}

private void Initialize()
{
CurRow = 0; nxtRow = 1;

// Setting a variable to the length of my double buffer array
int len = DOUBLE_BUFFER[0].length;


for ( int i = 0; i < len; ++i)
{
// Initializing my DOUBlE_BUFFER to 0
DOUBLE_BUFFER[0][i] = 0;
DOUBLE_BUFFER[1][i] = 0;
}

// ** Middle bit ***
DOUBLE_BUFFER[CurRow][(len/2)] = 1;
}


public void reset()
{
Initialize();
}

public int CellCount()
{
return DOUBLE_BUFFER[0].length;
}

public byte[] GetCurRow()
{

return DOUBLE_BUFFER[CurRow].clone();

}

public int GetRowSize()
{
return RowSize;
}

public void TimeStep()
{

for(int i=1; i < DOUBLE_BUFFER[0].length-1; i++)
{
DOUBLE_BUFFER[nxtRow][i] = rules[ Map(i)];

//System.out.print(DOUBLE_BUFFER[CurRow][i]);

CurRow = 1 - CurRow; nxtRow = 1 - nxtRow;


}

System.out.print("\n");

}

private int Map(int Pos)
{
int n = 0;
for (int i = Pos-1; i <= Pos+1; ++i)
{
n *=2;
n += DOUBLE_BUFFER[CurRow][i] % 2;

}

return n;
}

private void jbInit() throws Exception {
}


}


class Test_CA
{
private int n = 50;

public Test_CA()
{
CA_1D2S ca = new CA_1D2S(n);
if (ca.GetRowSize()!= n)
{
System.out.print("ca.GetCutRow() !=50\n");
return;
}

}


}

Dear Sir: The program you had on there called SimpleModel has the wrong algorithm. It is plotting rule 222. Under the method NextGen you have this comment:

// Set the array list element to an asterix when one or the
// other neighbour is an asterix, but not both.

Those are not the rules that you want. Rule 30 looks like this in binary:
00011110

You want to simulate this situation according to Mr. Wolfram.
111 110 101 100 011 010 001 000 This is converted to the next row
0 0 0 1 1 1 1 0 = 30



You have to reflect that in your rectangle drawing method. Ex.

for (int i=0; i<=80; i++) {
if ((arlPrev.get(i) == ASTERIX) && (i > 0) && (i < 80)) {
// byte 1
if (arlPrev.get(i-1).equals(ASTERIX) && (arlPrev).get(i+1).equals(ASTERIX)) {
arList.set(i, BLANKS);
}
// byte 2
if (arlPrev.get(i-1).equals(ASTERIX) && (arlPrev.get(i+1)).equals(BLANKS)){
arList.set(i,BLANKS);
}
// byte 5
if (arlPrev.get(i-1).equals(BLANKS) && (arlPrev.get(i+1)).equals(ASTERIX)){
arList.set(i,ASTERIX);
}


etc.

After those changes it ought to work. At least I got it to. Good luck.

Dear Sir: Ignore a good part of what I had written. SimpleModel was one of my old programs, not yours! It's been a while since I worked with that stuff. I didn't recognize one of my programs. However the algorithm works and when I made changes for Rule 30, the random patterns pop up. There are probably other approaches, ie. bit pushing. I just used simple line by line processing of blanks and astericks in an ArrayList to build the next generation. Hope that wasn't too confusing! Good Luck!

Hey

The only part that i need to implement is the actual mapping of the bits. I need to get the pattern to output. Can you show me how you coded it?