rxSymInvChol function

Get Omega^-1 and derivatives

rxSymInvChol(
  invObjOrMatrix,
  theta = NULL,
  type = "cholOmegaInv",
  thetaNumber = 0L
)

Arguments

• invObjOrMatrix: Object for inverse-type calculations. If this is a matrix, setup the object for inversion rxSymInvCholCreate() with the default arguments and return a reactive s3 object. Otherwise, use the inversion object to calculate the requested derivative/inverse.

• theta: Thetas to be used for calculation. If missing (NULL), a special s3 class is created and returned to access Omega^1

  objects as needed and cache them based on the theta that is used.

• type: The type of object. Currently the following types are supported:

  • cholOmegaInv gives the Cholesky decomposition of the Omega Inverse matrix.

  • omegaInv gives the Omega Inverse matrix.

  • d(omegaInv) gives the d(Omega^-1) withe respect to the theta parameter specified in thetaNumber.

  • d(D) gives the d(diagonal(Omega^-1)) with respect to the theta parameter specified in the thetaNumber

    parameter

• thetaNumber: For types d(omegaInv) and d(D), the theta number that the derivative is taken against. This must be positive from 1 to the number of thetas defining the Omega matrix.

Returns

Matrix based on parameters or environment with all the matrixes calculated in variables omega, omegaInv, dOmega, dOmegaInv.

Author(s)

Matthew L. Fidler