funm:  Matrix equivalent of function 'name'

Usage:    B = funm(A, name)
where    A = square non-singular matrix, provisionally
real-valued
B = square result matrix
name = string, name of function to apply to A.
args = any arguments to pass to function 'name'
The function must accept a vector and apply
element-wise to that vector.

Example:  To compute sqrtm(A), you could use funm(A, 'sqrt')

Note that you should not use funm for 'sqrt', 'log' or 'exp'; instead
use sqrtm, logm and expm which are more robust. Similarly,
trigonometric and hyperbolic functions (cos, sin, tan, cot, sec, csc,
cosh, sinh, tanh, coth, sech, csch) are better handled by thfm(A,
name), which defines them in terms of the more robust expm.