Java Float floatToFloat16() Method

The Float.floatToFloat16() method in Java is used to convert a float value to its closest binary16 floating-point representation, encoded in a short.

Table of Contents

1. Introduction
2. floatToFloat16() Method Syntax
3. Examples
   • Converting a float to Binary16
   • Handling Special Values
4. Real-World Use Case
5. Conclusion

Introduction

The Float.floatToFloat16() method is a static method in the Float class in Java. It converts a float value to the closest binary16 (half-precision floating-point) representation, encoded in a short. This method is useful for applications that require storage or transmission of floating-point numbers in a compact format.

floatToFloat16()() Method Syntax

The syntax for the Float.floatToFloat16() method is as follows:

public static short floatToFloat16(float f)

• f: The float value to be converted to binary16.

The method returns:

• The binary16 floating-point value, encoded in a short, that is closest in value to the argument.

Examples

Converting a float to Binary16

The floatToFloat16() method can be used to convert a float value to its binary16 representation.

Example

public class FloatToFloat16Example {
    public static void main(String[] args) {
        float floatValue = 1.0f;
        short binary16Value = Float.floatToFloat16(floatValue);

        System.out.printf("Binary16 value of %.1f: 0x%04X%n", floatValue, binary16Value);
    }
}

Output:

Binary16 value of 1.0: 0x3C00

In this example, the float value 1.0f is converted to the binary16 representation 0x3C00.

Handling Special Values

The floatToFloat16() method can handle special values such as positive infinity, negative infinity, and NaN.

Example

public class SpecialValuesExample {
    public static void main(String[] args) {
        float posInf = Float.POSITIVE_INFINITY;
        float negInf = Float.NEGATIVE_INFINITY;
        float nan = Float.NaN;

        System.out.printf("Binary16 value of POSITIVE_INFINITY: 0x%04X%n", Float.floatToFloat16(posInf));
        System.out.printf("Binary16 value of NEGATIVE_INFINITY: 0x%04X%n", Float.floatToFloat16(negInf));
        System.out.printf("Binary16 value of NaN: 0x%04X%n", Float.floatToFloat16(nan));
    }
}

Output:

Binary16 value of POSITIVE_INFINITY: 0x7C00
Binary16 value of NEGATIVE_INFINITY: 0xFC00
Binary16 value of NaN: 0x7E00

In this example, the method correctly converts the special values POSITIVE_INFINITY, NEGATIVE_INFINITY, and NaN to their corresponding binary16 representations.

Real-World Use Case

Converting Float Values for Compact Storage

In a real-world application, you might need to convert float values to their binary16 representations for compact storage or transmission.

Example

import java.nio.ByteBuffer;

public class CompactStorageExample {
    public static void main(String[] args) {
        float[] floatValues = {1.0f, -2.0f, 3.14f, 1e10f};

        ByteBuffer buffer = ByteBuffer.allocate(floatValues.length * 2); // Each short is 2 bytes

        for (float value : floatValues) {
            short binary16Value = Float.floatToFloat16(value);
            buffer.putShort(binary16Value);
        }

        buffer.flip(); // Prepare the buffer for reading

        while (buffer.hasRemaining()) {
            System.out.printf("Stored binary16 value: 0x%04X%n", buffer.getShort());
        }
    }
}

Output:

Stored binary16 value: 0x3C00
Stored binary16 value: 0xC000
Stored binary16 value: 0x4248
Stored binary16 value: 0x7BFF

In this example, float values are converted to their binary16 representations and stored in a byte buffer for compact storage.

Conclusion

The Float.floatToFloat16() method in Java provides a straightforward way to convert float values to their binary16 (half-precision floating-point) representations. By understanding how to use this method, you can efficiently handle tasks that involve converting and storing floating-point numbers in a compact format in your Java applications. Whether you are dealing with normal values or special cases, the floatToFloat16() method provides a reliable solution for these tasks.