CSE 1400 Applied Discrete Mathematics Relations
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چکیده
A relation ∼ describes how things are connected. That a thing a is related to a thing b can be represented by 1. An ordered pair (a, b). 2. An directed edge a• •b . 3. Or more commonly, simply using relational notation a ∼ b. A relation is 1. A set G of ordered pairs. 2. A directed graph G of nodes and edges. 3. A matrix of True and False values. Higher-dimensional relations among a, b, c or more parameters can be defined. Higher-dimensional relations occur as tables in relational databases and as data in multi-variable problems. Relations and Their Graphs A relation is a set of ordered pairs. A relation can be pictured of as a graph G.
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