rule 30 finite automaton

[msl6]

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;
}

}


}

[goksanen]

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.

[goksanen]

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!

[msl6]

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?