MomentDist {RFOC}

Distance Between Moment Tensors

Description

Calculate the distance between moment tensors based on quaternions.

Usage

MomentDist(E1, E2)

Arguments

E1

Moment tensor

E2

Moment tensor

Details

Moment tensors should be right handed.

Value

angle in degrees

Author(s)

Jonathan M. Lees<[e-mail]>

References

Tape and Tape, 2012

See Also

forcerighthand, testrightHAND

Examples

Mtens = c(-0.412, 0.084, 0.328 ,0.398, -1.239, 1.058)
M1 = matrix(c(Mtens[1], Mtens[4], Mtens[5], Mtens[4], Mtens[2],
Mtens[6], Mtens[5],Mtens[6], Mtens[3]), ncol=3, nrow=3, byrow=TRUE)



Mtens = c(5.054, -2.235, -2.819, -0.476, 5.420, 5.594)
M2 = matrix(c(Mtens[1], Mtens[4], Mtens[5], Mtens[4], Mtens[2],
Mtens[6], Mtens[5],Mtens[6], Mtens[3]), ncol=3, nrow=3, byrow=TRUE)

E1 = eigen(M1)

###  make sure these are a right handed system,
###   ie x1 cross x2 = x3


E2 = eigen(M2)

###  make sure these are a right handed system,
###   ie x1 cross x2 = x3
testrightHAND(E1$vectors) 
testrightHAND(E2$vectors) 

E1$vectors = forcerighthand(E1$vectors)

E2$vectors = forcerighthand(E2$vectors)


testrightHAND(E1$vectors) 
testrightHAND(E2$vectors) 

MomentDist(E1, E2)