rexpokit: R wrappers for EXPOKIT; other matrix functions
This package wraps some of the matrix exponentiation
utilities from EXPOKIT (http://www.maths.uq.edu.au/expokit/), a
FORTRAN library that is widely recommended for matrix
exponentiation (Sidje RB, 1998. "Expokit: A Software Package
for Computing Matrix Exponentials." ACM Trans. Math. Softw.
24(1): 130-156). EXPOKIT includes functions for exponentiating
both small, dense matrices, and large, sparse matrices (in
sparse matrices, most of the cells have value 0). Rapid matrix
exponentiation is useful in phylogenetics when we have a large
number of states (as we do when we are inferring the history of
transitions between the possible geographic ranges of a
species), but is probably useful in other ways as well.