$n =~ s/\.?0+$//;
Update: Thanks to dreadpiratepeter for spotting my stupid mistake.
The better option would be $n =~ s/\.\d*?0+$//;
Update2:
That worked with my test data but only because I wasn't using formatted strings so trailing 0s were already dealt with. Doh!
With a %x.yf formatted string the original approach will work fine.
jmcnamara came up with probably the best solution Re: Eliminating Trailing Zeros

In reply to Re: Eliminating Trailing Zeros by Lachesis
in thread Eliminating Trailing Zeros by Anonymous Monk

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