You can't make it more general until you understand how to use multi-dimensional data structures in Perl, which means learning how to use references. Start with perlreftut, and then if you need more depth, continue to perlref, perllol, and perldsc. These documents will be enlightening.

Eventually you will work toward an implementation where rather than giving each column a named array, you will have an array of rows, and each row element will hold a reference to an anonymous array of columns. ...or you might invert it so that the top level array represents columns, and each column element holds a reference to an anonymous array of row elements.