How to search element in Float Array using Index in Java?

Declaration :

public static int binarySearch(float[] a, int fromIndex, int toIndex, float key)

1	public static int binarySearch(float[] a, int fromIndex, int toIndex, float key)

Explanation :

Purpose	The java.util.Arrays.binarySearch(float[] a int fromIndex int toIndex float key) method searches a range of the specified array of floats for the specified value using the binary search algorithm. The range must be sorted before making this call.If it is not sorted the results are undefined.
Parameters	a ===> This is the array to be searched.
	fromIndex ===> This is the index of the first element (inclusive) to be searched.
	toIndex ===> This is the index of the last element (exclusive) to be searched.
	key ===> This is the value to be searched for.
Return Value	This method returns index of the search key if it is contained in the array else it returns (-(insertion point) - 1). The insertion point is the point at which the key would be inserted into the array; the index of the first element in the range greater than the key or toIndex if all elements in the range are less than the specified key.
Exception	IllegalArgumentException — if fromIndex > toIndex ,ArrayIndexOutOfBoundsException — if fromIndex < 0 or toIndex > a.length

Java Program : Example

Below example will explain java.util.Arrays.binarySearch() method.

package com.c4learn;
import java.util.Arrays;
public class ArrayDemo {
	public static void main(String[] args) {
		// Initialize unsorted float array
		float arr[] = { 5.1f, 10.1f, 20.1f, 15.1f };
		// Sorting array
		Arrays.sort(arr);
		// Printing the sorted float array
		System.out.println("The sorted float array is:");
		for (float num : arr) {
			System.out.println("Array Element is " + num);
		}
		// Enter the value to be searched
		float val = 15.1f;
		// Enter range of index
		int returnV = Arrays.binarySearch(arr, 0, 4, val);
		System.out.println("The index of element 15.1 is : " + returnV);
	}
}

package com.c4learn;

import java.util.Arrays;

public class ArrayDemo {

public static void main(String[] args) {

// Initialize unsorted float array

float arr[] = { 5.1f, 10.1f, 20.1f, 15.1f };

// Sorting array

Arrays.sort(arr);

// Printing the sorted float array

System.out.println("The sorted float array is:");

for (float num : arr) {

System.out.println("Array Element is " + num);

}

// Enter the value to be searched

float val = 15.1f;

// Enter range of index

int returnV = Arrays.binarySearch(arr, 0, 4, val);

System.out.println("The index of element 15.1 is : " + returnV);

}

Output of Program :

The sorted float array is:
Array Element is 5.1
Array Element is 10.1
Array Element is 15.1
Array Element is 20.1
The index of element 15.1 is : 2

The sorted float array is:

Array Element is 5.1

Array Element is 10.1

Array Element is 15.1

Array Element is 20.1

The index of element 15.1 is : 2

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