Question

我编写了以下代码，该代码应生成1行10列的输出矩阵。通过将nchrom标签替换为q，我在纠正循环之前确实正常工作，但现在生成以下错误代码：

Error in rmultinom(1, size * q/2, prob = c(num_chrom)) : 
  no positive probabilities

如果有人可以帮我确定代码中的问题所在，我将非常感激。我的代码目前如下：

randomdiv <- function(nchrom, ndivs, size) {
  chrom <- matrix(nrow = 1, ncol = ndivs)
 {q <- nchrom
  for (i in 1:ndivs)
  {
  {sz <- matrix(nrow = nchrom, ncol = ndivs)          
   for (j in 1:nchrom) {
    n <- size
  for (i in 1:ndivs)
  {
    old_subs <- rbinom (1, n, 0.5)          #roughly halving the number of subunits per chromosome, representing segregation of chromosomes
    num_chrom <- rep(1 / q, q)    #vector to determine probabilities for multinomial - based on number of chromosomes per cell 
    new_subs <- rmultinom(1, size * q / 2, prob = c(num_chrom))     #multinomial to generate randomness in number of new subunits translated per cell (based on ideal being half of the total subunit pool)

    total_subs <- cbind(old_subs, new_subs)    #required step to allow ifelse function to properly work on individual rows
    m <- as.matrix(ifelse(total_subs[,1]>0, total_subs[,1] + total_subs[,2], total_subs[,1]))  #ifelse function to ensure that if a chromosome reaches 0 subunits, there will be no new subunits added to that chromosom

    zeros <- colSums(m==0)     #calculates number of zeros in the columns of m and will form a vector (2 values will be shown - only interested in the first for m[1,1])
    k <- c(-1, 1)
    s <- sample(k, zeros[1], replace = TRUE)  #random samples taken from -1 and  - number of samples is equal to the number of zeros that have occurred 
    new_nchrom <- q + sum(s)   #Sum of samples determines the number of chromosomes to add or remove from the cell (random element)

    chrom[,i] <- new_nchrom    #Inserts new number of chromosomes into the matrix for output
    q <- new_nchrom

    sz[j,i] <- m[1,1]      #puts in m matrix as the next column in sz matrix - need to keep a matrix of subunit numbers because the number of subunits reaching 0 determines changes in chromosome number
    n <- m
  }
}
}
 }
 }
 return (chrom)
 }

>randomdiv(10, 10, 3)

rmultinom错误 - 没有正面的可能性

0 个答案: