
Distance Functions in Digital Geometry 37
Reprinted from Sadhana 18(1993), P. P. Das and B. N. Chatterji, Digital Distance Geometry: A Survey, 159–187,
Copyright (1993), with permission from Indian Academy of Sciences.
FIGURE 2.4: A minimal O(2) or 18-path between two points (2,-7,5) and
(-8,-4,13) in 3-D.
the algorithm, z ∈ Σ
n
∩N eb(y; N(·)), is chosen if Π
∗
(y, 0) is a concatenation
of Π
∗
(y, z) and Π
∗
(z, 0) (evidently, |Π
∗
(y, 0)| = |Π
∗
(y, z)| + |Π
∗
(z, 0)|). In
Algorithm 3 we illustrate such a choice for O(m)-neighborhood set for d
n
m
distance.
2.2.3 Distances and Metrics
In Z
n
, Euclidean distance E
n
is defined as follows:
Definition 2.11. In n-D, E
n
: Z
n
×