--- /dev/null
+import java.util.Random;
+import java.text.NumberFormat;
+import java.lang.Math;
+import java.io.*;
+
+/** Class representing matrix with methods for matrix algebra
+ * Copylefted by: Harvie 2oo9 ( http://blog.harvie.cz/ )
+ * @author Thomas Harvie Mudrunka (mudruto1)
+ * @version 1.0
+ */
+
+class Matrix implements Serializable {
+ public float[][] matrix;
+ public final int x, y;
+ private Random rnd = new Random();
+
+ /** Construct new zero matrix described by (rows,cols) */
+ Matrix(int i, int j) {
+ x = i;
+ y = j;
+ matrix = new float[x][y];
+ for(i = 0;i < x;i++) for(j = 0;j < y;j++) matrix[i][j] = 0;
+ }
+
+ /** Construct new matrix from (2d_array) */
+ Matrix(float[][] m) {
+ x = m.length;
+ y = m[0].length;
+ matrix = m;
+ }
+
+ /** Return matrix as multiline String ready to output */
+ public String toString() {
+ String out = new String("");
+ for(int i = 0;i < x;i++) {
+ out += "|\t";
+ for(int j = 0;j < y;j++) out += (NumberFormat.getInstance().format(matrix[i][j])+"\t");
+ out += "|\n";
+ }
+ return out;
+ }
+
+ /** Print matrix to console */
+ public void print() {
+ System.out.println(this.toString());
+ }
+
+ /** Randomize matrix with numbers x, where: 0 <= x < max */
+ public void randomize(int max) {
+ for(int i = 0;i < x;i++) for(int j = 0;j < y;j++) matrix[i][j] = rnd.nextInt(max);
+ }
+
+ /** Compare size of this and another matrix */
+ public boolean compatible(Matrix m) {
+ if(m.x == this.x && m.y == this.y) return true;
+ System.err.println("Cannot add/subtract/multiply two matrices with different sizes!");
+ return false;
+ }
+
+ /** Add another matrix to this and return result */
+ public Matrix add(Matrix m) {
+ if(!compatible(m)) return null;
+ Matrix o = new Matrix(x,y);
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) o.matrix[i][j] += this.matrix[i][j];
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) o.matrix[i][j] += m.matrix[i][j];
+ return o;
+ }
+
+ /** Subtract another matrix from this and return result */
+ public Matrix subtract(Matrix m) {
+ if(!compatible(m)) return null;
+ Matrix o = new Matrix(x,y);
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) o.matrix[i][j] += this.matrix[i][j];
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) o.matrix[i][j] -= m.matrix[i][j];
+ return o;
+ }
+
+ /** Scalar-multiply this matrix by another one and return result */
+ public Matrix multiply(Matrix m) {
+ if(!compatible(m)) return null;
+ Matrix o = new Matrix(x,y);
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) o.matrix[i][j] += this.matrix[i][j];
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) o.matrix[i][j] *= m.matrix[i][j];
+ return o;
+ }
+
+ /** Matrix-multiply this matrix by another one and return result */
+ public Matrix mmultiply(Matrix m) {
+ if(this.y != m.x) {
+ System.err.println("Cannot multiply those two matrices!");
+ return null;
+ }
+ Matrix o = new Matrix(this.x,m.y);
+ for(int i = 0;i < o.x;i++) for(int j = 0;j < o.y;j++) {
+ for(int z = 0;z < this.y;z++) o.matrix[i][j] += this.matrix[i][z] * m.matrix[z][j];
+ }
+ return o;
+ }
+
+ /** Return matrix representing this matrix with swapped rows a and b */
+ public Matrix swap_rows(int a, int b) {
+ Matrix o = new Matrix(x,y);
+ int i, j;
+ for(i = 0;i < o.x;i++) for(j = 0;j < o.y;j++) o.matrix[i][j] += this.matrix[i][j];
+ float tmp[] = o.matrix[a];
+ o.matrix[a] = o.matrix[b];
+ o.matrix[b] = tmp;
+ return o;
+ }
+
+ /** Return determinant of this matrix */
+ public double determinant() {
+ System.err.println("TODO: Determinant!");
+ return 0;
+ }
+
+ /*public float SIM_MIN(float a, float b) {
+ return (a < b ? a : b);
+ }
+
+ public double fabs(double a) {
+ return Math.abs(a);
+ }*/
+
+ /** Return matrix representing upper triangle format of this matrix */
+ public Matrix echelon() {
+ System.err.println("Reducing to echelon row form is not working properly!");
+ //return null;
+ Matrix o = new Matrix(x,y);
+ int i, j;
+ for(i = 0;i < o.x;i++) for(j = 0;j < o.y;j++) o.matrix[i][j] += this.matrix[i][j];
+
+ for(int row = x; row >= 0; row--) {
+ //reduceRow(row);
+ double multiplier;
+ for(j=row+1; j < y; j++) {
+ if(o.matrix[row][j] != 0) {
+ multiplier = -o.matrix[row][j];
+ //addRow(j, row, multiplier);
+ //(int fromRow, int toRow, double mult)
+ for(i=0; i<y; i++) {
+ o.matrix[row][i] += o.matrix[j][i]*multiplier;
+ }
+ }
+ }
+ }
+ /*int lead = 0;
+
+ for(int r = 0; r < x; r++) {
+ if(x <= lead) {
+ return o;
+ }
+ i = r;
+ while(o.matrix[i][lead] == 0) {
+ i++;
+ if(x == i) {
+ i = r;
+ lead++;
+ if(y == lead) {
+ return o;
+ }
+ }
+ }
+ o = o.swap_rows(i, r);
+ for(j = 0;j < y; j++) o.matrix[r][j] /= o.matrix[r][lead];
+ for(int row = 0; row < x; row++)
+ {
+ if(row != r)
+ {
+ for(int l = 0; l < y; l++)
+ o.matrix[row][l] -= o.matrix[i][lead] * o.matrix[r][l];
+ }
+ }
+ lead++;
+ }
+ */
+
+ return o;
+ }
+
+ /** Serialize this object to file specified by its name (and path) */
+ public boolean save(String file) {
+ try {
+ ObjectOutputStream os = new ObjectOutputStream(new FileOutputStream(file));
+ os.writeObject(this);
+ os.close();
+ } catch (Exception e) {
+ e.printStackTrace();
+ return false;
+ }
+ return true;
+ }
+
+ /** Deserialize and return Matrix object from file specified by its name (and path) */
+ public static Matrix load(String file) {
+ Matrix m = null;
+ try {
+ ObjectInputStream is = new ObjectInputStream(new FileInputStream(file));
+ m = (Matrix) is.readObject();
+ is.close();
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ return m;
+ }
+
+
+}
+
+/** Class demonstrating usage of Matrix class */
+public class matice {
+ public static void main(String[] argv) {
+ System.out.println("You has matrix! Follow the black habit ;o)\n");
+
+ String file = "f.matrix";
+
+ System.out.println("Created matrix F and saved to file "+file+" =");
+ Matrix f = new Matrix(3,3); f.randomize(2); f.print();
+ f.save(file);
+
+ System.out.println("Loaded matrix G from file "+file+" =");
+ Matrix g = Matrix.load(file); g.print();
+
+ System.exit(0);
+
+ System.out.println("Created matrix A =");
+ Matrix a = new Matrix(3,3); a.randomize(2); a.print();
+
+ System.out.println("Created matrix B =");
+ Matrix b = new Matrix(new float[][] {
+ {1, 2, 3},
+ {4, 5, 6},
+ {7, 8, 9}
+ });
+ b.print();
+
+ /*System.out.println("Row Echelon form of B =");
+ b.echelon().print();
+ */
+
+ System.out.println("A + B =");
+ a.add(b).print();
+
+ System.out.println("A - B =");
+ a.subtract(b).print();
+
+ System.out.println("A * B =");
+ a.multiply(b).print();
+
+ System.out.println("Swap rows 0 and 1 of matrix B =");
+ b.swap_rows(0,1).print();
+
+ System.out.println("Created matrix C =");
+ Matrix c = new Matrix(3,4); c.randomize(20); c.print();
+
+ System.out.println("Created matrix D =");
+ Matrix d = new Matrix(4,2); d.randomize(10); d.print();
+
+ System.out.println("C . D =");
+ c.mmultiply(d).print();
+ }
+}
+
+/* Echelon debug:
+
+B: matrix(
+ [1,2,3],
+ [4,5,6],
+ [7,8,9]
+);
+
+echelon(B) = matrix(
+[1,2,3],
+[0,1,2],
+[0,0,0]
+)
+
+**********************************/
+
+
+/* Example:
+
+0 ;) harvie@harvie-ntb prg $ javac matice.java; java matice
+You has matrix! Follow the black habit ;o)
+
+Created matrix A =
+| 0 0 0 |
+| 0 0 1 |
+| 1 1 0 |
+
+Created matrix B =
+| 8 9 8 |
+| 7 9 6 |
+| 7 4 8 |
+
+A + B =
+| 8 9 8 |
+| 7 9 7 |
+| 8 5 8 |
+
+A - B =
+| -8 -9 -8 |
+| -7 -9 -5 |
+| -6 -3 -8 |
+
+A * B =
+| 0 0 0 |
+| 0 0 6 |
+| 7 4 0 |
+
+Created matrix C =
+| 19 12 2 7 |
+| 1 3 8 12 |
+| 7 5 13 4 |
+
+Created matrix D =
+| 8 2 |
+| 7 8 |
+| 8 4 |
+| 5 7 |
+
+C . D =
+| 287 191 |
+| 153 142 |
+| 215 134 |
+
+*/
GIT.Harvie.CZ / mirrors / Programs.git / blobdiff