How much memory does float occupy?

Occupies 4 bytes of memory. The float type occupies 4 bytes of memory in most programming languages. In the IEEE 754 standard, the float type uses 32-bit representation. This 32-bit storage space is divided into three parts: sign bit, exponent code and mantissa. The storage structure of float requires 1 bit to represent the symbol, 8 bits to represent the exponent code, and 23 bits to represent the mantissa. Therefore, the memory size occupied by the float type is 1 8 23 = 32 bits = 4 bytes.

# Operating system for this tutorial: Windows 10 system, Dell G3 computer.

The memory size occupied by the float type may vary in different programming languages. In Java, the float type occupies 4 bytes (32 bits), and it also occupies 4 bytes in C language. Below I will explain in detail why the float type occupies 4 bytes of memory.

In computers, all data are stored and processed in binary form. The storage of floating point numbers usually uses the IEEE 754 standard, which defines the representation method and operation rules of floating point numbers.

In the IEEE 754 standard, the float type uses 32 bits. This 32-bit storage space is divided into three parts: sign bit, exponent code and mantissa.

The sign bit is represented by 1 bit and is used to represent the positive and negative signs of floating point numbers. 0 represents a positive number and 1 represents a negative number.

The exponent code is represented by 8 bits and is used to store the exponent part of the floating point number. The exponent range is -127 to 128, where -127 and 128 are reserved values ​​used to represent special cases (such as positive infinity and negative infinity).

The mantissa is represented by 23 bits and is used to store the decimal part of the floating point number. The mantissa ranges from 0 to 1, in binary decimal form.

Based on the number of bits allocated above, we can calculate the memory size occupied by the float type. The sign bit occupies 1 bit, the exponent occupies 8 bits, and the mantissa occupies 23 bits. Therefore, the memory size occupied by the float type is 1 8 23 = 32 bits = 4 bytes.

It should be noted that although the float type occupies 4 bytes in memory, its effective number is only 23 bits, so there may be a loss of precision when performing floating point operations. question. If you need higher precision, you can use the double type, which occupies 8 bytes (64 bits) and has a valid number of 52 bits.

To summarize, the float type occupies 4 bytes of memory in most programming languages. This is because its storage structure requires 1 bit to represent the symbol, 8 bits to represent the exponent, and 23 bits to represent the mantissa. However, it should be noted that the precision of the float type is relatively low. If higher precision is required, you can consider using the double type.

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