x1 = rnorm(n,0)
x2 = rnorm(n,0)
# true event time
T = rweibull(n, shape=1, scale=lambdaT*exp(-beta1*x1-beta2*x2))
C = rweibull(n, shape=1, scale=lambdaC) #censoring time
time = pmin(T,C) #observed time is minof censored and true
event = time==T # set to 1 if event isobserve