float
Purpose: float is designed to store fractional numbers or numbers with decimal points.
Size: It occupies 4 bytes (32 bits) of memory.
Precision: float offers approximately 6 to 7 decimal digits of precision. This means that after a certain number of decimal places, the value may become less accurate due to the limitations of its 32-bit representation.
Range: The approximate range for float is from 1.4E-45 to 3.4E+38.
Literal Suffix: When assigning a literal value to a float variable, it is necessary to append the letter f or F to the number.
double
Purpose: It is primarily used for storing decimal numbers that require a high degree of precision and a wide range of values.
This makes it suitable for scientific calculations, financial applications, and complex mathematical computations.
Size: A double occupies 8 bytes (64 bits) of memory.
Precision: It offers higher precision compared to the float data type, which is a single-precision 32-bit floating-point number.
Range: The approximate range for double values is from 4.9e-324 to 1.7e+308.
Default Choice: For most decimal values in Java, double is the generally recommended and default choice due to its balance of precision and range.
Primitive data types are the fundamental building blocks for storing and manipulating data in the Java programming language. They are predefined by the language itself and represent basic values like numbers, characters, and true/false statements. Unlike non-primitive data types, they are not objects and don’t have any associated methods.
primitive data types offer a set of predefined, immutable building blocks for storing and manipulating fundamental values.
These simple and efficient types have fixed sizes, reside directly in memory for faster access, and avoid object overhead for memory efficiency.
However, their limited functionality and lack of inheritance capabilities mean they are well-suited for basic data operations but may not be ideal for complex data structures or advanced functionalities, which are better handled by non-primitive data types like classes and interfaces.
Primitive data types in Java excel in performance and memory efficiency.
Their direct memory access, lack of object overhead, and smaller sizes allow for faster operations, comparisons, and manipulations by the CPU. Additionally, their efficient caching contributes to quicker retrieval.
Furthermore, since they don’t require object-related memory allocations, they consume less memory compared to non-primitive data types.
However, it’s essential to remember that choosing the right data type involves a balance between performance and memory usage.
While primitive types offer these advantages, their capabilities and range may be limited compared to non-primitive types like String.
Therefore, selecting the appropriate data type requires careful consideration of both performance requirements and memory constraints.
Primitive Data Types
byte: Stores small whole numbers (8 bits) ranging from -128 to 127.
short: Stores whole numbers (16 bits) ranging from -32,768 to 32,767.
int: The most commonly used integer type (32 bits) with a range of -2,147,483,648 to 2,147,483,647.
long: Stores larger whole numbers (64 bits) ranging from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.
float: Stores single-precision floating-point numbers (32 bits) for decimal values, offering less precision than double.
double: Stores double-precision floating-point numbers (64 bits) for decimal values, offering more precision than float.
char: Stores single characters using Unicode (16 bits).
boolean: Represents true or false (1 bit).
Float and double are two primitive data types in Java that are used to store floating-point numbers. Floating-point numbers are numbers that can have a decimal point, such as 3.14159 or 1.23456789e10.
Float is a 32-bit floating-point number, which means that it can store up to 7 decimal digits accurately.
Double is a 64-bit floating-point number, which means that it can store up to 15 decimal digits accurately.
Float
The float keyword in Java is a primitive data type, and its size limit is 4 byte or 32 bits (1 byte = 8 bits) single-precision IEEE 754 (Standard for Floating-Point Arithmetic) floating-point number, that is it can allow up to 6 digits precision after the decimal.
We use this float keyword to declare the variable and methods. It usually stores the value in decimals or fractions.
We use this Float data type, if we want to use the memory efficiently, or if the number is in the small range. As the Float consumes less memory in comparison to the Double data type. By default, Java treats any decimal or float numbers as double type, so in case, if we want to define any value as float, we need to manually typecast it using the 'f' or 'F' keyword in the suffix of the number.
For example, if we define a float number as:
float weight = 70.645;
In the above code in Java, the declaration of the float variable will throw a compilation error of possible lossy conversion from double to float, but we can fix the error by adding the character 'f' or 'F' in the suffix of the number.
float weight = 70.645f;
or
float weight = 70.645F;
double
The double keyword in Java is also a primitive data type, and its size limit is 8 byte or 64 bits double-precision IEEE 754 floating-point number, that is it can allow up to 15 digits precision after the decimal. . We often use this keyword when we have a larger floating value and if we want a more precise and accurate value. As the Double data type consumes more memory in comparison to the Float data type, but it gives more accurate values of up to 15 digits of precision than the float data type. By default, Java considers any decimal or float values of double type, so we do not need to typecast any decimal value to double manually. Hence, adding the suffix 'd' or 'D' in the number is optional in the case of Double data type values.
For example, we define a double number as:
double weight = 70.6458763;
or
double weight = 70.6458763d;
or
double weight = 70.6458763D;
Key Difference Between Float and Double in Java
The main difference between Java Float and Double is their precision and range.
Float is a 32-bit floating-point number, which means that it can store up to 7 decimal digits accurately while Double is a 64-bit floating-point number, which means that it can store up to 15 decimal digits accurately.
Second major difference lies in their memory usage. Double variables take up twice as much memory as float variables.
Difference Between Float and Double in Java
Now let us look at the Float vs Double comparison table.
BASIS FOR COMPARISON Floatand Double
Definition The float keyword in Java is a primitive data type, single-precision 32-bit.
The double keyword in Java is a primitive data type, double-precision 64-bit
Usage The float data type is less precise, that is, it is used where accuracy is not a big factor, and storage is limited.
The double data type is more precise, that is, it is used where accuracy is a big factor, and we want to avoid data compression or bit loss.
Storage: The float data type consumes 4 byte or 32 bits for storing a variable
The double data type consumes 8 byte or 64 bits for storing a variable
Benefits
The float data type have ample support libraries. Open source and community development. The double data type has more uses for web development, and is more web focused
Academics The float data type is a 32-bit IEEE 754 floating point A double is a 64-bit IEEE 754 floating point.
Precision The float data type precision is up to 6 to 7 decimal digits. The double data type can provide precision up to 15 to 16 decimal digits.
Range The float data type range lies between 3.4e-038 to 3.4e+038, and it has a lower range as compared to the double data type. The double data type range lies between 1.7e-308 to 1.7e+308, and it has a higher range as compared to the float data type.
Keyword Used To define a number as float, we mention the float keyword. To define a number as double, we mention the double keyword.
Wrapper Class The float data type wrapper class is java.lang.Float. The double data type wrapper class is java.lang.Double.
Default Data Type Java does not use float as the default data type for floating point numbers. Java use the double as the default data type for floating point numbers.
Data Loss If we convert any float type value from float to double, there will be no data loss. If we convert any double type value from double to float, there will be data loss.
Suffix The float data type uses 'f' or 'F' as a suffix. It is mandatory to mention the suffix if we want the number to be of float type. The double data type uses 'd' or 'D' as a suffix. It is not mandatory to mention the suffix if we want the number to be of double type.
Representation 28.96f or 28.96F 12.5 or 12.5D or
Reffer
Www.Scaler.com
Float vs Double — Explanation:
Size :4 bytes 8 bytes.
Accuracy: 7 digits approx ,15 digits approx.
Speed: Faster (uses less memory) Little slower (more memory used)
Example:
float a = 3.1415926f;
double b = 3.141592653589793;
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