SHEEP is one of the earliest interactive symbolic computation systems. It is specialized for computations with

tensor In mathematics, a tensor is an algebraic object that describes a multilinear relationship between sets of algebraic objects associated with a vector space. Tensors may map between different objects such as vectors, scalars, and even other ...

s, and was designed for the needs of researchers working with

general relativity General relativity, also known as the general theory of relativity, and as Einstein's theory of gravity, is the differential geometry, geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of grav ...

and other theories involving extensive tensor calculus computations. SHEEP is a

freeware Freeware is software, often proprietary, that is distributed at no monetary cost to the end user. There is no agreed-upon set of rights, license, or EULA that defines ''freeware'' unambiguously; every publisher defines its own rules for the free ...

package (copyrighted, but free for educational and research use). The name "SHEEP" is pun on the

Lisp Algebraic Manipulator The Lisp Algebraic Manipulator (also known as LAM) was created by Ray d'Inverno, who had written Atlas LISP Algebraic Manipulation (ALAM was designed in 1970).

or ''LAM'' on which SHEEP is based. The package was written by Inge Frick, using earlier work by Ian Cohen and

Ray d'Inverno Ray or RAY may refer to: Fish * Ray (fish), any cartilaginous fish of the superorder Batoidea * Ray (fish fin anatomy), the bony or horny spine on ray-finned fish Science and mathematics * Half-line (geometry) or ray, half of a line split at an ...

, who had written ALAM - Atlas LISP Algebraic Manipulation in earlier (designed in 1970). SHEEP was an

interactive Across the many fields concerned with interactivity, including information science, computer science, human-computer interaction, communication, and industrial design, there is little agreement over the meaning of the term "interactivity", but mo ...

computer package whereas LAM and ALAM were

batch processing Computerized batch processing is a method of running software programs called jobs in batches automatically. While users are required to submit the jobs, no other interaction by the user is required to process the batch. Batches may automatically ...

languages. Jan E. Åman wrote an important package in SHEEP to carry out the Cartan-Karlhede algorithm. A more recent version of SHEEP, written by Jim Skea, runs under Cambridge Lisp, which is also used for

REDUCE Reduction, reduced, or reduce may refer to: Science and technology Chemistry * Reduction (chemistry), part of a reduction-oxidation (redox) reaction in which atoms have their oxidation state changed. ** Organic redox reaction, a redox reacti ...

Notes

External links

SHEEP download directory
at

Queen Mary, University of London Queen Mary University of London (QMUL, or informally QM, and formerly Queen Mary and Westfield College) is a public research university in Mile End, East London, England. It is a member institution of the federal University of London. Today, ...

Some sources of info on SheepReview article by M.A.H.MacCallum in "Workshop on Dynamical Spacetimes and Numerical Relativity"
edited by Joan Centrella Tensors {{relativity-stub

See also

Notes

External links