The signal_table() function modifies the data.table class to
work with electrical signal data. The input should be a data set of equal
number of rows. It will add a column of index positions called sample if
it does not already exist.
signal_table(...)is_signal_table(x)
An object of class signal_table, which is an extension of the
data.table class. The sample column is invariant and will always be
present. The other columns represent additional channels.
A list of equal lengths
data.frame A data frame of signal data