### Java Math ceil() example

In this guide, you will learn about the Java Math ceil() example method in Java programming and how to use it with an example.

## 1. Java Math ceil() example Method Overview

### Definition:

The ceil() method of Java's Math class returns the smallest (closest to negative infinity) double value that is greater than or equal to the argument and is equal to a mathematical integer.

### Syntax:

``Math.ceil(a)``

### Parameters:

- a: A double value whose ceiling value is to be determined.

### Key Points:

- If the argument is NaN, positive infinity, or negative infinity, then the result will be NaN, positive infinity, or negative infinity, respectively.

- If the argument value is already equal to a mathematical integer, then the result will be the same as the argument.

- The return type is double, even for whole number results.

## 2. Java Math ceil() example Method Example

``````public class CeilExample {
public static void main(String[] args) {
double[] values = {42.1, 42.7, -42.1, -42.7};

for (double value : values) {
// Calculate the ceiling value
double ceilValue = Math.ceil(value);
System.out.println("Ceiling value of " + value + ": " + ceilValue);
}

// Special case for NaN
System.out.println("Ceiling value of NaN: " + Math.ceil(Double.NaN));
}
}
``````

### Output:

```Ceiling value of 42.1: 43.0
Ceiling value of 42.7: 43.0
Ceiling value of -42.1: -42.0
Ceiling value of -42.7: -42.0
Ceiling value of NaN: NaN
```

### Explanation:

In the example:

1. For 42.1 and 42.7, their ceiling values are the next whole numbers, which are 43.0.

2. For negative numbers like -42.1 and -42.7, their ceiling values move closer to zero, resulting in -42.0.

3. The method returns NaN when passed NaN as an argument, adhering to the principle that operations with NaN generally result in NaN.