List object cannot be coerced to type 'double

Question

I use R and when I try to run the following code: ``` f = scan(file="c:\myfile.txt", sep=' ', what=list('numeric')) MY_MATRIX.M = matrix(f, ncol = 4, byrow = TRUE) Var.names = c('column1','column2', 'column3', 'column4') colnames(MY_MATRIX.M) = Var.names TEST = data.frame(MY_MATRIX.M) t1 = TEST[which(TEST[,4] == 0, arr.ind = TRUE),] t2 = TEST[which(TEST[,4] == 1, arr.ind = TRUE),] ``` I have the following error: ``` Error in which(TEST[,4] == 0, arr.ind = TRUE : (list) object cannot be coerced to type 'double' ``` My file has 4 columns and consist of numbers like an array. Can anyone give me a hand on solving the problem ?

Accepted Answer

The problem you're experiencing is due to the argument `what=list(numeric)`. You want to tell `R` that the file has just `numeric` values, not that it contains lists with numeric elements. So just use `what=numeric`, or don't use `what` at all.

I don't import text files often, but when I do, I prefer `read`.

List object cannot be coerced to type 'double

Solution

Problem