Size theory

In mathematics, size theory studies the properties of topological spaces endowed with R k {displaystyle mathbb {R} ^{k}} -valued functions, with respect to the change of these functions. More formally, the subject of size theory is the study of the natural pseudodistance between size pairs.A survey of size theory can be found in .The beginning of size theory is rooted in the concept of size function, introduced by Frosini. Size functions have been initially used as a mathematical tool for shape comparison in computer vision and pattern recognition.