adjust asreml to work in newer versions

[bonifazi]

No description provided.

[bonifazi]

Newer version of asreml seems to have an header.
In that case check that indeed first line is all character or not all numeric, then proceed with the logic of skipping the header in fread.

suggestion from chatgpt (too redundant IMO, see if can be improved):

Read the first line of the file

first_line <- readLines(infile, n = 1)

Check if the first line contains numeric data

if (all(is.numeric(scan(text = first_line, quiet = TRUE)))) {

First line contains numeric data, no header, skip = 0

sln <- fread(infile,
header = FALSE,
stringsAsFactors = FALSE,
strip.white = TRUE,
col.names = col_names,
colClasses = list(character = c(1, 2), double = c(3:4))
)
} else {

First line contains non-numeric data, assume it's a header, skip = 1

sln <- fread(infile,
header = FALSE,
skip = 1,
stringsAsFactors = FALSE,
strip.white = TRUE,
col.names = col_names,
colClasses = list(character = c(1, 2), double = c(3:4))
)
}