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Shape Representative (Orbit Representative)

Source: R/alignment.R
shape.representative.Rd

Compute the canonical representative of a curve in a quotient space. Depending on the quotient, this factors out reparameterization, translation, and/or scale.

Usage

shape.representative(
  f,
  argvals = NULL,
  quotient = c("reparameterization", "translation", "scale")
)

Arguments

f

Numeric vector of curve values.

argvals

Numeric vector of evaluation points. If NULL, defaults to seq(0, 1, length.out = length(f)).

quotient

Character: the quotient space. One of "reparameterization", "translation", or "scale".

Value

A list with components:

representative

The canonical representative curve

representative.srsf

SRSF of the representative

gamma

Warping function to the representative

translation

Translation applied (0 for reparameterization-only)

scale

Scale factor applied (1 for reparameterization-only)

References

Srivastava, A. and Klassen, E. (2016). Functional and Shape Data Analysis. Springer.

See also

shape.distance, shape.mean

Examples

# \donttest{
t <- seq(0, 1, length.out = 50)
f <- sin(2 * pi * t)
rep <- shape.representative(f, argvals = t)
# }