Think in java 答案_Chapter 4_Exercise 19

阅前声明: http://blog.csdn.net/heimaoxiaozi/archive/2007/01/19/1487884.aspx

/****************** Exercise 19 *****************
* Write a method that creates and initializes a
* two-dimensional array of double. The size of
* the array is determined by the arguments of
* the method, and the initialization values are
* a range determined by beginning and ending
* values that are also arguments of the method.
* Create a second method that will print the
* array generated by the first method. In main()
* test the methods by creating and printing
* several different sizes of arrays.
***********************************************/
public class E19_TwoDDoubleArray {
  public static double[][] twoDDoubleArray(
    int xLen, int yLen,
    double valStart, double valEnd){
    double[][] array = new double[xLen][yLen];
    double increment =
      (valEnd - valStart)/(xLen * yLen);
    double val = valStart;
    for(int i = 0; i < array.length; i++)
      for(int j = 0; j < array[i].length; j++) {
        array[i][j] = val;
        val += increment;
      }
    return array;
  }
  public static void printArray(double[][] array){
    for(int i = 0; i < array.length; i++) {
      for(int j = 0; j < array[i].length; j++)
        System.out.print(" " + array[i][j]);
      System.out.println();
    }
  }
  public static void main(String args[]) {
    double[][] twoD =
      twoDDoubleArray(4, 6, 47.0, 99.0);
    printArray(twoD);
    System.out.println("**********************");
    double[][] twoD2 =
      twoDDoubleArray(2, 2, 47.0, 99.0);
    printArray(twoD2);
    System.out.println("**********************");
    double[][] twoD3 =
      twoDDoubleArray(9, 5, 47.0, 99.0);
    printArray(twoD3);
  }
}

//+M java E19_TwoDDoubleArray

**The step value for the initialization range is calculated by dividing the range by the number of elements in the array.