Since homotheties are determined by the fixed point, called the center of the homothety, and by the similitude ratio λ, we shall denote by hP,λ the homothety with center P and similitude ratio λ.
(commutative algebra,Bourbakist) A homomorphism from a module over a ring to itself of the form for some fixed (especially when ; is said to be the ratio of the homothety, by analogy with the geometric case).
Synonyms
(isotropic scaling transformation with a fixed point):homothecy, homogeneous dilation, homothetic transformation