Constructor for tabfreq objects.
The function tabfreq creates a tabfreq object from
a data frame or a matrix giving allele frequencies for a single population in the Journal of Forensic Sciences (JFS) format for population genetic data.
Whene multiple populations are considered, data shall be given as a list, where each element is either a matrix or a data frame in the JFS format, and the
populations names must be specified.
The function as.tabfreq is an alias for the tabfreq function.
is.tabfreq tests if an object is a valid tabfreq object.
Note: to get the manpage about tabfreq, please type
'class ? tabfreq'.