|
|
|
|
|
Unit BallIn mathematics, the open unit ball in a normed vector space for a given norm is - .
The closed unit ball on under is - .
The 'shape' of the unit ball is entirely dependent on the chosen norm; it may well have 'corners', and for example may look like −1,1n, in the case of the norm l∞ in Rn. The round ball is understood as the usual Hilbert space norm, based in the finite dimensional case on the Euclidean distance; its boundary is what is usually meant by the unit sphere. See also:
|
 |
| |
|
|