Common Integral Data Types
| Bits | Name | Range (assuming two's complement for signed) | Decimal Digits (approx.) | Uses | Implementations | ||||
|---|---|---|---|---|---|---|---|---|---|
| C/C++ | C# | Pascal and Delphi | Java | SQL | |||||
| 4 | nibble, semioctet | Signed: From −8 to 7, from −(23) to 23 − 1 | 1 | Binary-coded decimal, single decimal digit representation. | n/a | n/a | n/a | n/a | |
| Unsigned: From 0 to 15 which equals 24 − 1 | 2 | ||||||||
| 8 | byte, octet | Signed: From −128 to 127, from −(27) to 27 − 1 | 3 | ASCII characters | int8_t, char | sbyte | Shortint | byte | tinyint |
| Unsigned: From 0 to 255 which equals 28 − 1 | 3 | uint8_t, char | byte | Byte | n/a | unsigned tinyint | |||
| 16 | halfword, word, short | Signed: From −32,768 to 32,767, from −(215) to 215 − 1 | 5 | UCS-2 characters | int16_t, short, int | short | Smallint | short | smallint |
| Unsigned: From 0 to 65,535 which equals 216 − 1 | 5 | uint16_t | ushort | Word | char | unsigned smallint | |||
| 32 | word, long, doubleword, longword, int | Signed: From −2,147,483,648 to 2,147,483,647, from −(231) to 231 − 1 | 10 | UTF-32 characters, True Color with alpha, FourCC, ActionScript int | int32_t, int, long | int | LongInt; Integer | int | int |
| Unsigned: From 0 to 4,294,967,295 which equals 232 − 1 | 10 | uint32_t | uint | LongWord; DWord; Cardinal | n/a | unsigned int | |||
| 64 | word, doubleword, longword, long long, quad, quadword, int64 | Signed: From −9,223,372,036,854,775,808 to 9,223,372,036,854,775,807, from −(263) to 263 − 1 | 19 | Very large numbers | int64_t, long, long long | long | Int64 | long | bigint |
| Unsigned: From 0 to 18,446,744,073,709,551,615 which equals 264 − 1 | 20 | uint64_t | ulong | UInt64; QWord | n/a | unsigned bigint | |||
| 128 | octaword, double quadword | Signed: From −170,141,183,460,469,231,731,687,303,715,884,105,728 to 170,141,183,460,469,231,731,687,303,715,884,105,727, from −(2127) to 2127 − 1 | 39 | Complex scientific calculations | C: only available as non-standard compiler-specific extension | n/a | n/a | n/a | |
| Unsigned: From 0 to 340,282,366,920,938,463,463,374,607,431,768,211,455 which equals 2128 − 1 | 39 | ||||||||
| n | n-bit integer (general case) |
Signed: (−(2n−1)) to (2n−1 − 1) | ⌈(n − 1) log10 2⌉ | Ada range -2**(n-1)..2**(n-1)-1 |
|||||
| Unsigned: 0 to (2n−1) | ⌈n log10 2⌉ | Ada range 0..2**n-1, Ada mod 2**n |
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- ^ Not all SQL dialects have unsigned datatypes.
- The sizes of short, int, and long in C/C++ are dependent upon the implementation of the language; dependent on data model, even short can be anything from 16-bit to 64-bit. For some common platforms:
- On older, 16-bit operating systems, int was 16-bit and long was 32-bit.
- On 32-bit Linux, DOS, and Windows, int and long are 32-bits, while long long is 64-bits. This is also true for 64-bit processors running 32-bit programs.
- On 64-bit Linux, int is 32-bits, while long and long long are 64-bits.
- The sizes of Delphi's Integer and Cardinal are not guaranteed, varying from platform to platform; usually defined as LongInt and LongWord respectively.
- ^ Java does not directly support arithmetic on char types. The results must be cast back into char from an int.
Different CPUs support different integral data types. Typically, hardware will support both signed and unsigned types but only a small, fixed set of widths.
The table above lists integral type widths that are supported in hardware by common processors. High level programming languages provide more possibilities. It is common to have a ‘double width’ integral type that has twice as many bits as the biggest hardware-supported type. Many languages also have bit-field types (a specified number of bits, usually constrained to be less than the maximum hardware-supported width) and range types (which can represent only the integers in a specified range).
Some languages, such as Lisp, Smalltalk, REXX and Haskell, support arbitrary precision integers (also known as infinite precision integers or bignums). Other languages which do not support this concept as a top-level construct may have libraries available to represent very large numbers using arrays of smaller variables, such as Java's BigInteger class or Perl's "bigint" package. These use as much of the computer’s memory as is necessary to store the numbers; however, a computer has only a finite amount of storage, so they too can only represent a finite subset of the mathematical integers. These schemes support very large numbers, for example one kilobyte of memory could be used to store numbers up to 2466 decimal digits long.
A Boolean or Flag type is a type which can represent only two values: 0 and 1, usually identified with false and true respectively. This type can be stored in memory using a single bit, but is often given a full byte for convenience of addressing and speed of access.
A four-bit quantity is known as a nibble (when eating, being smaller than a bite) or nybble (being a pun on the form of the word byte). One nibble corresponds to one digit in hexadecimal and holds one digit or a sign code in binary-coded decimal.
Read more about this topic: Integer (computer Science)
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