Java double Array

double Array in Java

Java double array is used to store double data type values only. The default value of the elements in a double array is 0.

With the following java double array examples you can learn

  • how to declare java double array
  • how to assign values to java double array
  • how to get values from java double array

Initializing a double Array in Java

Arrays are declared with [] (square brackets). If you put [] (square brackets) after any variable of any type only that variable is of type array remaining variables in that declaration are not array variables those are normal variables of that type.

If you put [] (square brackets) after any data type all the variables in that declaration are array variables. All the elements in the array are accessed with index. The array element index is starting from 0 to n-1 number i.e. if the array has 5 elements then starting index is 0 and ending index is 4.

// declares an array of doubles
double[] doubleArray;

What is the Length of an Array in Java ?

In Java all the arrays are indexed and declared by int only. That is the size of an array must be specified by an int value and not long or short. All the arrays index beginning from 0 to ends at 2147483646. You can store elements upto 2147483647. If you try to store long (big) elements in array, you will get performance problems. If you overcome performance problems you should go to java collection framework or simply use Vector.

Syntax :
                        < data type > < variable >[];
                        < data type >[] < variable >
			    

Java double Array Example

/* Java double Array Example */
/* Save with file name DoubleArray.java */

public class DoubleArray
{
	public static void main(String args[])
	{
		//JAVA DOUBLE ARRAY DECLARATION

		double a[];

		//MEMORY ALLOCATION FOR JAVA DOUBLE ARRAY

		a = new double[4];

		//ASSIGNING ELEMENTS TO JAVA DOUBLE ARRAY

		a[0] = 100000d;

		a[1] = 300000d;

		a[2] = 400000d;

		a[3] = 786777d;

		//JAVA DOUBLE ARRAY OUTPUT

		System.out.println("Java double Array Example");

		for(int i=0;i<a.length;i++)
		{
			System.out.println("Element at Index : "+ i + " " + a[i]);
		}
	}
}
				    

Following Java double array example you can learn how to assign values to Java double array at the time of declaration.

How to assign values to Java double array at the time of declaration

/* How to assign values to Java double array at the time of declaration Example */
/* Save with file name DoubleArray2.java */

public class DoubleArray2
{
	public static void main(String args[])
	{
		//JAVA DOUBLE ARRAY DECLARATION

		double a[] = {100000d,300000d,400000d,786777d};

		//JAVA DOUBLE ARRAY OUTPUT

		System.out.println("Java double Array Example");

		for(int i=0;i<a.length;i++)
		{
			System.out.println("Element at Index : "+ i + " " + a[i]);
		}
	}
}
				    

Following Java double array example you can learn how to declare Java double array with other Java double array variables.

How to declare Java double array with other Java double array variables

/* How to declare Java double array with other Java double array variables Example */
/* Save with file name DoubleArray3.java */

public class DoubleArray3
{
	public static void main(String args[])
	{
		//JAVA DOUBLE ARRAY DECLARATION

		double a[], a2;

		//MEMORY ALLOCATION FOR JAVA DOUBLE ARRAY

		a = new double[4];

		//ASSIGNING ELEMENTS TO JAVA DOUBLE ARRAY

		a[0] = 100000d;

		a[1] = 300000d;

		a[2] = 400000d;

		a[3] = 786777d;

		a2 = 333333d;

		//DOUBLE ARRAY OUTPUT

		System.out.println("Java double Array Example");

		System.out.println("a2 value is : "+a2);

		for(int i=0;i<a.length;i++)
		{
			System.out.println("Element at Index : "+ i + " " + a[i]);
		}
	}
}
				    

Following Java double array example you can learn how to assign Java double array to other Java double array.

How to assign Java double array to other Java double array

/* How to assign Java double array to other Java double array Example */
/* Save with file name DoubleArray4.java */

public class DoubleArray4
{
	public static void main(String args[])
	{
		//JAVA DOUBLE ARRAY DECLARATION

		double[] a, a2; //a AND a2 ARE ARRAY VARIABLES

		//MEMORY ALLOCATION FOR JAVA DOUBLE ARRAY

		a = new double[4];

		//ASSIGNING ELEMENTS TO JAVA DOUBLE ARRAY

		a[0] = 100000d;

		a[1] = 300000d;

		a[2] = 400000d;

		a[3] = 786777d;

		//ASSIGNING a ARRAY TO a2 ARRAY VARIABLE

		a2 = a;

		//JAVA DOUBLE ARRAY OUTPUT

		System.out.println("Java double Array Example");

		System.out.println("a array values");

		for(int i=0;i<a.length;i++)
		{
			System.out.println("Element at Index : "+ i + " " + a[i]);
		}

		System.out.println("a2 array values");

		for(int i=0;i<a2.length;i++)
		{
			System.out.println("Element at Index : "+ i + " " + a2[i]);
		}
	}
}