What's the easiest way to export a CSV to Excel with Ruby?

I'm using Ruby 1.9 for this. I need to convert Rub开发者_StackOverflow社区y arrays into a Excel spreadsheet document (xls).

I use two gems to export to Excel-readable formats: Spreadsheet (can create/parse .xls) and FasterCSV (faster, but as far as I can remember doesn't work with .xls files)

I've had excellent results with WriteExcel (which is a Ruby port of a Perl library of the same name).

Csv files would be the fastest if you just want to export values