1     
2    import java.util.Vector; 
3     
4    /** 
5     * This method is used in the generation of Ramanujan-LPS graph vertices. Since the vertices of Ramanujan-LPS graph are 
6     * some precalculated matrices, they have to be calculated. 
7     * Created by IntelliJ IDEA. 
8     * User: Max B. 
9     * Date: Nov 4, 2004 
10    * Time: 9:33:04 PM 
11    */ 
12   public class MatrixList { 
13    
14       /** 
15        * A list used to save the Matrices created. 
16        */ 
17       private Vector list; 
18    
19       /** 
20        * C-tor of the class. 
21        * The duty of the c-tor is to initialie whatever values need initialization and vreate a 
22        * list of matrixes which are not alike in the sence of multiplication 
23        * 
24        * @param q 
25        */ 
26       public MatrixList(int q) { 
27           list = new Vector(); 
28           this.generateMatrixList(q); 
29           System.out.println("Creation of the Matrix list finished"); 
30    
31       } 
32    
33    
34       /** 
35        * Public accessor 
36        * @param i 
37        * @return 
38        */ 
39       public MyMatrix MatrixAt(int i){ 
40           return (MyMatrix)( list.elementAt(i)); 
41       } 
42    
43    
44       /** 
45        * Public accessor 
46        * @return 
47        */ 
48       public Vector getList() { 
49           return list; 
50       } 
51    
52       /** 
53        * Prints the matrixes on the list. 
54        */ 
55       public void printMatrixList() { 
56           for (int i = 0; i < list.size(); i++) { 
57               ((MyMatrix) (list.elementAt(i))).print(); 
58           } 
59       } 
60    
61       /** 
62        * This method generates the matrixes to be entered to the list themselves and enters them to the list. 
63        * @param q 
64        */ 
65       public void generateMatrixList(int q) { 
66           MyMatrix m; 
67           int cnt1 = 0; 
68           int cnt2 = 0; 
69    
70           for (int i = 0; i < q; i++) { 
71               for (int j = 0; j < q; j++) { 
72                   for (int k = 0; k < q; k++) { 
73                       m = new MyMatrix(1, k, j, i); 
74                       cnt1++; 
75                       if (m.det() != 0) 
76                           list.addElement(m); 
77                       else 
78                           cnt2++; 
79                   } 
80               } 
81           } 
82    
83           for (int l = 0; l < q; l++) { 
84               for (int h = 0; h < q; h++) { 
85                   m = new MyMatrix(0, 1, h, l); 
86                   cnt1++; 
87                   if (m.det() != 0) 
88                       list.addElement(m); 
89                   else 
90                       cnt2++; 
91               } 
92           } 
93           System.out.println("Matrixes tried (q^3+ q^2) = " + cnt1); 
94           System.out.println("Matrixes skipped (det=0)  = " + cnt2); 
95       } 
96    
97       /** 
98        * This method checks wheather there are "proportional" matrices  in the list generated, if there are, then the list is wrong. 
99        * @return returns number of proportional matrices found, 0 for none. 
100       */ 
101      public int checkIntegrity() { 
102          MyMatrix m; 
103          int cnt = 0; 
104          for (int i = 0; i < list.size(); i++) { 
105              m = (MyMatrix) list.elementAt(i); 
106              for (int j = 0; j < list.size(); j++) { 
107                  if (j != i) 
108                      if (m.similar((MyMatrix) list.elementAt(j))) { 
109                          System.out.println("Similar matrices found : "); 
110                          m.print(); 
111                          ((MyMatrix) list.elementAt(j)).print(); 
112                          System.out.println("----------------------- "); 
113                          cnt++; 
114   
115                      } 
116              } 
117          } 
118          return cnt; 
119      } 
120   
121   
122      /** 
123       * @return returns the number of generated matrixes 
124       */ 
125      public int length() { 
126          return list.size(); 
127      } 
128   
129   
130  } 
131