curve_srvf_align {fdasrvf}R Documentation

Align Curves

Description

Aligns a collection of curves using the elastic square-root velocity (srvf) framework.

Usage

curve_srvf_align(
  beta,
  mode = "O",
  rotated = T,
  scale = F,
  maxit = 20,
  ms = "mean"
)

Arguments

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")

Value

Returns a list containing

betan

aligned curves

qn

aligned srvfs

betamean

mean curve

q_mu

mean SRVFs

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

data("mpeg7")
out = curve_srvf_align(beta[,,1,1:2],maxit=2) # note: use more shapes, small for speed
[Package fdasrvf version 1.9.7 Index]