Floating point numbers, also known as “floats,” are a data type in Java that allows us to represent fractional values. They are called “floating” because the decimal point can “float” around within the number, allowing for a greater range of values.
Java has two primitive data types for floating point numbers:
float is a single-precision floating point data type, which means it uses 32 bits to represent a number.
double is a double-precision floating point data type, which uses 64 bits to represent a number. The difference between the two is the level of precision they provide.
double has a higher level of precision, but also requires more memory to store.
You can declare a floating point variable in Java like this:
float myFloat = 3.14f; double myDouble = 3.14;
Note that when declaring a
float value, we must include the
f at the end of the number. If we do not include it, the value will be treated as a
double by default.
Floating point numbers are often used when performing calculations that require a high level of precision, such as scientific or financial applications. However, it’s important to keep in mind that floating point numbers are not always 100% accurate. Because they are stored as a finite number of bits, they can sometimes produce unexpected results when used in certain calculations.
One common issue with floating point numbers is called “round-off error.” This occurs when the number being stored is not an exact representation of the value, resulting in a small error. This error can accumulate over time, leading to inaccuracies in calculations.
To avoid these issues, it’s important to use the correct data type for our needs and to be aware of the potential limitations of floating point numbers.