我的矩阵填充代码给出了NA？

Question

I am trying to create a matrix of values from an equation inside of a for loop. I keep getting "NA" filled in all of the indices. How do I put the values from the y equation into the matrix steal ?

set.seed(1234)

row = 10
col = 100
p1 = list(runif(250, 0, 0.250))
p2 = list(runif( 500, 0.250, 0.750))
pBASP = list(runif(1000, 0, 1)) 

steal = matrix(data=NA, nrow=10, ncol=100)
as.data.frame(steal)

y = matrix(data=NA, nrow=10, ncol=100)
as.data.frame(y)

success <- function(p1, p2, pBASP) {

  for(i in 1:row) {  
    for(j in 1:col) {      
      y[i,j] <- (p1/p2) + pBASP

      if(y[i,j] > 0.750){        
        steal[i,j] <- y[i,j]        
      }      
    }  
  }

  return(steal)
}

#plot(y, hy, type="l", lty=2, xlab="y value",
# ylab="Density", main="Batting Average with RISP")

Answer 1

Are you able to run your function in the current form?

The problem is that p1 , p2 , and pBASP are all lists which makes this call to fail:

y[ i, j ] <- ( p1 / p2 ) + pBASP

To actually run it i had to access items within the lists. I do not know what's the purpose of the function so I only focused on making it run and accessed i th element of each list:

 y[ i, j ] <- ( p1[[1]][[i]] / p2[[1]][[i]] ) + pBASP[[1]][[i]]

This generates a result and actually populates the steal collection.

Also, is there any particular reason to create p1 , p2 , and pBASP as lists and not vectors (using c() function.) Making it vector would simplify the access syntax to this:

 y[ i, j ] <- ( p1[i] / p2[i] ) + pBASP[i]

Answer 2

Here's my "best guess" based on how I'm interpreting the code you've written. I'll modify my response if it doesn't capture what you're trying to do.

# I'm changing the dimensions of `p1` and `p2` to match the matrices:
p1 <- runif(10,  0, 0.25)
p2 <- runif(100, 0.25, 0.75)
pBASP <- matrix(runif(1000, 0, 1), ncol = 100, nrow = 10)

y <- outer(p1, p2, "/") + pBASP # this creates y without any loops

steal <- y  
steal[steal <= 0.75] <- NA # remove the values of steal that you don't want.