Plot the DLT curve based on the EWOC classical model
dlt_curve_d1classical(mtd, rho, theta, min_dose, max_dose, dose_set = NULL)
mtd: a numerical value indicating the true value of the parameter mtd.rho: a numerical value indicating the true value of the parameter rho.theta: a numerical value defining the proportion of expected patients to experience a medically unacceptable, dose-limiting toxicity (DLT) if administered the MTD.min_dose: a numerical value defining the lower bound of the support of the MTD.max_dose: a numerical value defining the upper bound of the support of the MTD.dose_set: a numerical vector of doses that probability of DLT will be calculated.