Bray-Curtis distance
The Bray-Curtis distance is the Manhattan distance divided by the sum of both vectors.
bray_curtis(x, y)
x, y |
Numeric vectors |
For two vectors x
and y
, the Bray-Curtis distance is defined
as
d(x, y) = \frac{∑_i |x_i - y_i|}{∑_i x_i + y_i}.
The Bray-Curtis distance is connected to many other distance measures in this package; we try to list some of the more important connections here. Relation to other definitions:
Equivalent to vegdist()
with method = "bray"
.
Equivalent to the braycurtis()
function in
scipy.spatial.distance
for positive vectors. They take the
absolute value of x_i + y_i in the denominator.
Equivalent to the braycurtis
and odum
calculators in
Mothur.
Equivalent to D_14 = 1 - S_17 in Legendre & Legendre.
The Bray-Curtis distance on proportions is equal to half the Manhattan distance.
The Bray-Curtis distance on presence/absence vectors is equal to the Sorenson index of dissimilarity.
The Bray-Curtis distance between x
and y
. The
Bray-Curtis distance is undefined if the sum of all elements in x
and y
is zero, in which case we return NaN
.
x <- c(15, 6, 4, 0, 3, 0) y <- c(10, 2, 0, 1, 1, 0) bray_curtis(x, y) # For proportions, equal to half the Manhattan distance bray_curtis(x / sum(x), y / sum(y)) manhattan(x / sum(x), y / sum(y)) / 2
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.