> Just to double check that I've understood everything here, does the "%.2f"..

This is covered under sprintf documentation, specifically in the paragraph "precision, or maximum width".

Anyway try it to see:

# pay attention to MSWin32 double quotes!

perl -e "printf qq($_\n),3.141592 for '%f','%.0f','%.1f','%.2f'"

3.141592
3
3.1
3.14
[download]

L*