PROJ (formerly PROJ.4) is a

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for performing conversions between

cartographic projection In cartography, map projection is the term used to describe a broad set of transformations employed to represent the two-dimensional curved surface of a globe on a plane. In a map projection, coordinates, often expressed as latitude and longitud ...

s. The library is based on the work of Gerald Evenden at the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

(USGS), but since 2019-11-26 is an

Open Source Geospatial Foundation The Open Source Geospatial Foundation (OSGeo), is a non-profit non-governmental organization whose mission is to support and promote the collaborative development of open geospatial technologies and data. The foundation was formed in February ...

(OSGeo) project maintained by the PROJ Project Steering Committee (PSC). The library also ships with

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s for performing these transformations from the command line.

History

The history of PROJ dates back to the late 1970s, and the first release of PROJ was developed by Gerald Evenden in the early 1980s as a Ratfor program. It was based on the General Cartographic Transformation Package or GCTP, which consisted of Fortran subroutines that could be used to project geographic data. The second release of PROJ from 1985 was rewritten in C to run on

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systems. The third release of PROJ from 1990, was expanded to support approximately 70 cartographic projections. Evenden further developed a fourth release in 1994, named PROJ.4. The last version maintained by Evenden was 4.3, released on September 24, 1995. After over four years of inactivity, Frank Warmerdam became the new maintainer and released version 4.4 on March 21, 2000. As of May 2008, PROJ became part of the MetaCRS project, a confederation of coordinate systems related projects under incubation with OSGeo. With the release of version 5.0 in February 2018, the software was renamed to PROJ, removing version four (".4") from the name. With the acquisition of the proj.org

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in June 2019, the project was also renamed as PROJ.

Ports

The string format that PROJ uses to describe coordinate systems and transformations, ''proj string'' or ''proj.4 string'', is widely used beyond PROJ proper. A wide variety of ports or bindings in other programming languages have been developed. * Bindings based on the PROJ library (libproj) exist for Python, Ruby, Rust, Golang, Julia, TCL, MySQL, Excel, Visual Basic, and Fortran. PROJ.4 additionally had bindings for R and

Perl Perl is a family of two high-level, general-purpose, interpreted, dynamic programming languages. "Perl" refers to Perl 5, but from 2000 to 2019 it also referred to its redesigned "sister language", Perl 6, before the latter's name was offic ...

. * Proj4JS (

JavaScript JavaScript (), often abbreviated as JS, is a programming language that is one of the core technologies of the World Wide Web, alongside HTML and CSS. As of 2022, 98% of websites use JavaScript on the client side for webpage behavior, of ...

) and Proj4J (

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) are ports of PROJ into different programming languages now managed under MetaCRS.

References

External links

* {{Official website Geographic coordinate systems Free computer libraries C (programming language) libraries

History

Ports

See also

References

External links