curve_karcher_mean {fdasrvf} | R Documentation |
Karcher Mean of Curves
Description
Calculates Karcher mean or median of a collection of curves using the elastic square-root velocity (srvf) framework.
Usage
curve_karcher_mean(
beta,
mode = "O",
rotated = TRUE,
scale = TRUE,
lambda = 0,
maxit = 20,
ms = "mean"
)
Arguments
beta |
Array of sizes |
mode |
Open ( |
rotated |
Optimize over rotation (default = |
scale |
scale curves to unit length (default = |
lambda |
A numeric value specifying the elasticity. Defaults to |
maxit |
maximum number of iterations |
ms |
string defining whether the Karcher mean ( |
Value
Returns a list containing
mu |
mean srvf |
beta |
centered data |
betamean |
mean or median curve |
type |
string indicating whether mean or median is returned |
v |
shooting vectors |
q |
array of srvfs |
gam |
array of warping functions |
cent |
centers of original curves |
len |
length of curves |
len_q |
length of srvfs |
mean_scale |
mean length |
mean_scale_q |
mean length srvf |
E |
energy |
qun |
cost function |
References
Srivastava, A., Klassen, E., Joshi, S., Jermyn, I., (2011). Shape analysis of elastic curves in euclidean spaces. Pattern Analysis and Machine Intelligence, IEEE Transactions on 33 (7), 1415-1428.
Examples
out <- curve_karcher_mean(beta[, , 1, 1:2], maxit = 2)
# note: use more shapes, small for speed