
Get the numeric bin offset which was set as global variable bin_offset
Source: R/global_var.R
bin_offset2.RdThe global variable bin_offset will be used to rename bin ID by adding an
amount defined in bin_offset to each bin's original ID in df[[bin_col]].
We wish to do this because sometimes water bin and feed bin share the same
ID, and we want to differentiate water bins from feed bins using this bin_offset.