using DelimitedFiles
function quick_and_dirty_read(filename)
m = readdlm(filename; comments = true, comment_char = '#')
vector_rows = isempty.(m[:, 2])
Int.(m[.!vector_rows, :]), Float64.(m[ vector_rows, 1]) # modify types or do something else if necessary
end
reads the file, do the concatenation, then write it out similarly.