Affine may describe any of various topics concerned with connections or affinities.
It may refer to: * Affine, a relative by marriage in law and anthropology *

Affine cipher The affine cipher is a type of monoalphabetic substitution cipher, where each letter in an alphabet is mapped to its numeric equivalent, encrypted using a simple mathematical function, and converted back to a letter. The formula used means that eac ...

, a special case of the more general substitution cipher * Affine combination, a certain kind of constrained linear combination * Affine connection, a connection on the tangent bundle of a differentiable manifold * Affine Coordinate System, a coordinate system that can be viewed as a Cartesian coordinate system where the axes have been placed so that they are not necessarily orthogonal to each other. See

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

. * Affine differential geometry, a geometry that studies differential invariants under the action of the special affine group * Affine gap penalty, the most widely used scoring function used for sequence alignment, especially in bioinformatics * Affine geometry, a geometry characterized by parallel lines * Affine group, the group of all invertible affine transformations from any affine space over a field ''K'' into itself * Affine logic, a substructural logic whose proof theory rejects the structural rule of contraction * Affine representation, a continuous group homomorphism whose values are automorphisms of an affine space *

Affine scheme In commutative algebra, the prime spectrum (or simply the spectrum) of a ring ''R'' is the set of all prime ideals of ''R'', and is usually denoted by \operatorname; in algebraic geometry it is simultaneously a topological space equipped with the ...

, the spectrum of prime ideals of a commutative ring ** Affine morphism, a morphism of schemes such that the pre-image of an open affine subscheme is affine * Affine space, an abstract structure that generalises the affine-geometric properties of Euclidean space * Affine

, a tensor belonging to an affine coordinate system *

Affine transformation In Euclidean geometry, an affine transformation or affinity (from the Latin, ''affinis'', "connected with") is a geometric transformation that preserves lines and parallelism, but not necessarily Euclidean distances and angles. More generall ...

, a transformation that preserves the relation of parallelism between lines

See also