This function provides the fitting options for the reReg() function.
reReg.control(
  eqType = c("logrank", "gehan", "gehan_s"),
  solver = c("BB::dfsane", "BB::BBsolve", "BB::BBoptim", "optimx::optimr",
    "dfoptim::hjk", "dfoptim::mads", "optim", "nleqslv::nleqslv"),
  tol = 1e-07,
  init = list(alpha = 0, beta = 0, eta = 0, theta = 0),
  boot.parallel = FALSE,
  boot.parCl = NULL
)a character string indicating whether the log-rank type estimating equation or the Gehan-type estimating equation (when available) will be used.
a character string specifying the equation solver to be used for root search.
a numerical value specifying the absolute error tolerance in root search.
a list contains the initial guesses used for root search.
an logical value indicating whether parallel computation will be
applied when se = "boot" is specified in reReg().
an integer value specifying the number of CPU cores to be used when
parallel = TRUE. The default value is half the CPU cores on the current host.