Titlebook: Categories for the Working Mathematician; Saunders Mac Lane Textbook 1978Latest edition Springer Science+Business Media New York 1978 Adjo

Basilar-Artery

Special Limits,This chapter covers two useful types of limits (and colimits): The filtered limits, which are limits taken over preordered sets which are directed (and, more generally, over certain filtered categories), and the “ends”, which are limits obtained from certain bifunctors, and which behave like integrals.

聲明

Structures in Categories,In this chapter, we will examine several conceptual developments. We start with the idea of an “internal” category, described by diagrams within an ambient category. We then go on to study the sequences of composable arrows in a category — they constitute the “nerve” of the category, which turns out to be a simplicial set.

ELUDE

Introduction, of arrows. Each arrow . : . → . represents a function; that is, a set ., a set ., and a rule . ? . which assigns to each element . ∈ . an element . ∈ .; whenever possible we write . and not .(.), omitting unnecessary parentheses.

狗舍

Constructions on Categories,n a set-theoretical basis in the next section. Hence for this section a category will not be described by sets (of objects and of arrows) and functions (domain, codomain, composition) but by axioms as in § I.1.

負(fù)擔(dān)

橫截,橫斷

Facet-Joints

cluster

誘導(dǎo)

Karin Bruckmüller,Ulrich Schrothn a set-theoretical basis in the next section. Hence for this section a category will not be described by sets (of objects and of arrows) and functions (domain, codomain, composition) but by axioms as in § I.1.

妨礙議事