[R] Bootstrap standard errors

[Rman]

I have this coding to help me work out the bootstrap standard errord for the
following array/matrix
dat <-
matrix(c(8,23,14,13,9,11,25,25,14,11,4,25,19,7,13,1,8,16,2,6,3,4,6,5,7),
nrow = 5, ncol=5, byrow=TRUE)

the function is:

mybootstrap <- function(dat, nr, nc, m)
{
  # dat is a two dimentional array
  # nr is the number of rows in the table
  # nc is the number of columns in the table
  # m is the number of bootstrap simulations
  x <- dat[,1]
  # Tries scored combinations (0-0, 0-1,...)
  y <- dat[,2]
  # Frequencies
  n <- sum(y)
  r <- nr * nc
  v <- matrix(0., r, m)
  prob <- y / sum(y)
  z <- vector(mode = "numeric", length = r)
  for (k in 1.:m){
    y <-sample(x, n, replace = T, prob)
    for (i in 1.:r){
      z[i] <- length(y[y == x[i]])
    }
    w <- matrix(0., nr, nc)
    for(i in 1:nr){
      w[i, 1:nc] <- z[(nc * (i - 1) + 1) : (nc * i)]
    }
    rsum <- apply(w, 1., sum)
    csum <- apply(w, 2., sum)
    u <- matrix(0., nr, nc)
    for(i in 1.:nr){
      for (j in 1.:nc){
        if(w[i,j] > 0.)
          u[i,j] <- (w[i,j] * 100.* n) / (rsum[i] * csum[j])
      }
    }
    a <- u[1, ]
    for(i in 2:nr){
      a <- c(a, u[i, ])
    }
    v[, k] <- a
  }
  stderr <- apply (v, 1., var)
  return(sqrt(stderr))
}

mybootstrap(dat, 5, 5, 500)

there are no errors as such but the numbers produced are too small,
incorrect and are reroduced. I am expecting numbers such as 18 or 21 etc not
0.00004

can anybody help me please.

thanks

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