[R] Weibull simulation- number of items to replace is not a multiple of replacement length

[Halabi, Anan]

Hi,
I write below code for simulation for weibull- estimating parameters by weibullMLE function,
Although I define metrix for the variables still I got this message: number of items to replace is not a multiple of replacement length
Any suggestion 

> est=matrix (NA, 2,2)
> se=matrix (NA, 2,2)
> for ( p in 1:2) {
+ sampleSize <- 20
+ shape.true <- 1.82
+ scale.true <- 987
+ sampWB <- urweibull(sampleSize, shape=shape.true, scale=scale.true, lb=0, ub=Inf)
+ sampWBmleWB <- weibullMLE(sampWB)
+ est[p]= sampWBmleWB$estimate
+ se [p]= sampWBmleWB$s
+ }
Warning messages:
1: In est[p] = sampWBmleWB$estimate :
  number of items to replace is not a multiple of replacement length
2: In se[p] = sampWBmleWB$s :
  number of items to replace is not a multiple of replacement length
3: In est[p] = sampWBmleWB$estimate :
  number of items to replace is not a multiple of replacement length
4: In se[p] = sampWBmleWB$s :
  number of items to replace is not a multiple of replacement length
> est
         [,1] [,2]
[1,] 1.507558   NA
[2,] 1.525856   NA
> se
          [,1] [,2]
[1,] 0.2513083   NA
[2,] 0.2709073   NA