Roxen xslt and date filtering

[Christopher Howard]

Hi. I'm still an XSLT newbie, but I am trying to use some XSLT in Roxen 
to transform an RSS feed into html. However, I want to do filtering 
based on the date, e.g., only display five entries with the most recent 
pubDate. Working from within a Roxen system, what are my options for 
date sorting/filtering?
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