Matrix exponential.

  EXPM(X) is the matrix exponential of X.  EXPM is computed using

  a scaling and squaring algorithm with a Pade approximation.

  Although it is not computed this way, if X has a full set

  of eigenvectors V with corresponding eigenvalues D, then

  [V,D] = EIGMNUFU2(X) and EXPM(X) = V*diag(exp(diag(D)))/V.

  See EXPM17M9S0VU, EXPM29NUL0FZ and EXPM38TPAWQ for alternative methods.



  EXPMO9OU2(X) (that's without the M) does it element-by-element.