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:
“Three forms I see on stretchers lying, brought out there untended
lying,
Over each the blanket spread, ample brownish woolen blanket,
Gray and heavy blanket, folding, covering all.”
—Walt Whitman (1819–1892)
“Computers are good at swift, accurate computation and at storing great masses of information. The brain, on the other hand, is not as efficient a number cruncher and its memory is often highly fallible; a basic inexactness is built into its design. The brain’s strong point is its flexibility. It is unsurpassed at making shrewd guesses and at grasping the total meaning of information presented to it.”
—Jeremy Campbell (b. 1931)