4: Mathematical Data Types
- Page ID
- 48250
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We have assumed that you’ve already been introduced to the concepts of sets, sequences, and functions, and we’ve used them informally several times in previous sections. In this chapter, we’ll now take a more careful look at these mathematical data types. We’ll quickly review the basic definitions, add a few more such as “images” and “inverse images” that may not be familiar, and end the chapter with some methods for comparing the sizes of sets.
- 4.1: Sets
- Informally, a set is a bunch of objects, which are called the elements of the set. The elements of a set can be just about anything: numbers, points in space, or even other sets. The conventional way to write down a set is to list the elements inside curly-braces.