You want printf:

while (<DATA>) {
  printf "%1.2f\n", $_;
}
__DATA__
86902
.50
2.
165.0
0.666666666

[download]

Update: Better sprintf, as has been pointed out

--
David Serrano

In reply to Re: How to give format to numbers? by Hue-Bond
in thread How to give format to numbers? by Anonymous Monk

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