| curve_karcher_mean {fdasrvf} | R Documentation |
Calculates Karcher mean or median of a collection of curves using the elastic square-root velocity (srvf) framework.
curve_karcher_mean( beta, mode = "O", rotated = T, scale = F, maxit = 20, ms = "mean" )
beta |
array (n,T,N) for N number of curves |
mode |
Open ("O") or Closed ("C") curves |
rotated |
Optimize over rotation (default = T) |
scale |
Include scale (default = F) |
maxit |
maximum number of iterations |
ms |
string defining whether the Karcher mean ("mean") or Karcher median ("median") is returned (default = "mean") |
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 |
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.
data("mpeg7")
out = curve_karcher_mean(beta[,,1,1:2],maxit=2) # note: use more shapes, small for speed