symmetrize: create a perfectly symmetric version of landmarks
Description
create a perfectly symmetric version of landmarks
Usage
symmetrize(x, pairedLM)
Arguments
x
k x m matrix or k x m x n array, with rows containing landmark coordinates
pairedLM
A X x 2 matrix containing the indices (rownumbers) of the
paired LM. E.g. the left column contains the lefthand landmarks, while the
right side contains the corresponding right hand landmarks.
Value
a symmetrized version of x
Details
the landmarks are reflected and relabled according to
pairedLM and then rotated and translated onto x.
Both configurations are then averaged to obtain a perfectly symmetric one.
References
Klingenberg CP, Barluenga M, and Meyer A. 2002. Shape analysis of symmetric
structures: quantifying variation among individuals and asymmetry. Evolution
56(10):1909-1920.
# NOT RUN {data(boneData)
left <- c(4,6,8)
right <- c(3,5,7)
pairedLM <- cbind(left,right)
symx <- symmetrize(boneLM[,,2],pairedLM)
# }# NOT RUN {deformGrid3d(symx,boneLM[,,2])
# }