Picture language

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In formal language theory, a picture language is a set of pictures, where a picture is a 2D array of characters over some alphabet.

Formal language set of strings of symbols that may be constrained by rules that are specific to it

In mathematics, computer science, and linguistics, a formal language consists of words whose letters are taken from an alphabet and are well-formed according to a specific set of rules.

For example, the language defines the language of rectangles composed of the character . This language contains pictures such as:

The study of picture languages was initially motivated by the problems of pattern recognition and image processing, but two-dimensional patterns also appear in the study of cellular automata and other parallel computing models. Some formal systems have been created to define picture languages, such as array grammars and tiling systems.

A formal system is used to infer theorems from axioms according to a set of rules. These rules used to carry out the inference of theorems from axioms are known as the logical calculus of the formal system. A formal system is essentially an "axiomatic system". In 1921, David Hilbert proposed to use such system as the foundation for the knowledge in mathematics. A formal system may represent a well-defined system of abstract thought. Spinoza's Ethics imitates the form of Euclid's Elements. Spinoza employed Euclidean elements such as "axioms" or "primitive truths", rules of inferences, etc., so that a calculus can be built using these.

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Quaternion group finite group with 8 elements, whose elements can be represented by multiplication of unit quaternions {±1, ±i, ±j, ±k}

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References

Arto Salomaa Finnish mathematician and computer scientist; academian of science (Academy of Finland), professor emeritus of mathematics (University of Turku)

Arto K. Salomaa is a Finnish mathematician and computer scientist. His research career, which spans over forty years, is focused on formal languages and automata theory.