This functions checks and packages the fitting options for
survreg
survreg.control(maxiter=30, rel.tolerance=1e-09,
toler.chol=1e-10, iter.max, debug=0, outer.max=10)
A list with the same elements as the input
maximum number of iterations
relative tolerance to declare convergence
Tolerance to declare Cholesky decomposition singular
same as maxiter
print debugging information
maximum number of outer iterations for choosing penalty parameters
survreg