In mathematics, the ε-covering number of a metric space (X, d), for some ε > 0, is the minimum number of balls of radius that are needed to cover X.
A related concept is the ε-packing number which is defined as the maximum number of disjoint balls of radius ε that fit into X.
Famous quotes containing the words covering and/or number:
“You had to have seen the corpses lying there in front of the school—the men with their caps covering their faces—to know the meaning of class hatred and the spirit of revenge.”
—Alfred Döblin (1878–1957)
“Of all reformers Mr. Sentiment is the most powerful. It is incredible the number of evil practices he has put down: it is to be feared he will soon lack subjects, and that when he has made the working classes comfortable, and got bitter beer into proper-sized pint bottles, there will be nothing left for him to do.”
—Anthony Trollope (1815–1882)