Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

Plan 9 Plan 9 or Plan Nine may refer to: Music * Plan 9 (band), a psychedelic rock band from Rhode Island * ''Plan 9'', an album by Big Guitars From Memphis with Rick Lindy * "Plan 9", a song on the 1993 album ''Gorgeous'' by electronica band 808 Stat ...

, and

Unix-like A Unix-like (sometimes referred to as UN*X or *nix) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-li ...

computer systems, factor is a utility for factoring an integer into its

prime factors A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways ...

History

''factor'' first appeared on 5th edition

Research Unix The term "Research Unix" refers to early versions of the Unix operating system for DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). History The term ''Resear ...

in 1974, as a "user maintained" utility (

section Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sign ...

6 of the manual). In the 7th edition in 1979, it was moved into the main "commands" section of the manual (section 1). From there, the ''factor'' utility was copied to all other variants of

, including commercial Unixes and

BSD The Berkeley Software Distribution or Berkeley Standard Distribution (BSD) is a discontinued operating system based on Research Unix, developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Be ...

. In some variants of Unix, it is classified as a "game" more than a serious utility, and therefore documented in section 6. A

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, ...

version of the ''factor'' utility was written for the

GNU GNU () is an extensive collection of free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any ...

project by Paul Rubin, in 1986. It is now available on all

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...

distributions as part of the

GNU Core Utilities The GNU Core Utilities or coreutils is a package of GNU software containing implementations for many of the basic tools, such as cat, ls, and rm, which are used on Unix-like operating systems. In September 2002, the ''GNU coreutils'' were cr ...

. In 2008, GNU ''factor'' started to use the GNU MP library for

arbitrary-precision arithmetic In computer science, arbitrary-precision arithmetic, also called bignum arithmetic, multiple-precision arithmetic, or sometimes infinite-precision arithmetic, indicates that calculations are performed on numbers whose digits of precision are l ...

, allowing it to factor integers of any size, not limited by the machine's native datatypes. The command is available as a separate package for Microsoft Windows as part of the

UnxUtils UnxUtils is a collection of ports of common GNU Unix-like utilities to native Win32, with executables only depending on the Microsoft C- runtime msvcrt.dll. The collection was last updated externally on April 15, 2003, by Karl M. Syring. ...

collection of

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and enterta ...

Win32 The Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces (APIs) available in the Microsoft Windows operating systems. The name Windows API collectively refers to several different platform implementations ...

ports A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Ha ...

of common GNU Unix-like utilities.

Syntax

factor

umber Umber is a natural brown earth pigment that contains iron oxide and manganese oxide. In its natural form, it is called raw umber. When calcined, the color becomes warmer and it becomes known as burnt umber. Its name derives from ''terra d'omb ...

The command can be used by supplying an integer value. Various projects, including simple ones such as printing prime numbers, are facilitated by using this command.

References

External links

GNU's factor manual pageFreeBSD's factor man page
{{Core Utilities commands Unix software Plan 9 commands