根据IEEE标准,浮点数以两种方式表示:
Precision | Base | Sign | Exponent | Significand |
Single precision | 2 | 1 | 8 | 23+1 |
Double precision | 2 | 1 | 11 | 52+1 |
1.单精度:
单精度是IEEE提出的用于表示浮点数的格式。它在计算机内存中占据32位。
2.双精度:
Double Precision也是IEEE给出的用于表示浮点数的格式。它在计算机内存中占据64位。
单精度和双精度之间的区别:
SINGLE PRECISION | DOUBLE PRECISION |
---|---|
In single precision, 32 bits are used to represent floating-point number. | In double precision, 64 bits are used to represent floating-point number. |
It uses 8 bits for exponent. | It uses 11 bits for exponent. |
In single precision, 23 bits are used for mantissa. | In double precision, 52 bits are used for mantissa. |
Bias number is 127. | Bias number is 1023. |
Range of numbers in single precision : 2^(-126) to 2^(+127) | Range of numbers in double precision : 2^(-1022) to 2^(+1023) |
This is used where precision matters less. | This is used where precision matters more. |
It is used for wide representation. | It is used for minimization of approximation. |
It is used in simple programs like games. | It is used in complex programs like scientific calculator. |
This is called binary32. | This is called binary64. |
有关详细信息,请参考浮点表示。