sub incdec {

  $number = shift;

  # do something if not /^\d*\.\d+$/

  return $number+1 if $number =~ /^\d+$/;

  $number =~ /\.(\d+)$/;

  return $number + ("1E-".length($1);
}

for $n (1, .004, 1.99, 1.79, 1.009999) {

  print "$n++ = ".incdec($n)."\n";
}
[download]

gives:

1++ = 2
0.004++ = 0.005
1.99++ = 2
1.79++ = 1.8
1.009999++ = 1.01
[download]

Update: use E notation

--
Steve Marvell

Thanks.

  (0.1 ** length($1)) could also be written:
 ("1E-" . length($1))

update: This is what I came up with:

$frac = shift;

$frac =~ s/(\d+).$/$1/;   # remove last digit & get fraction size
$frac +=  "1E-" . length($1);   # add 1E-(size) => 0.0001

print $frac;
[download]

Works for "0.123999", "10.12399" and ".12399"

The result is weird when the number does not have a fractional part, but that is not my case.

Don't reinvoke on the same variable...

(1++) ++ = 3
(0.004++) ++ = 0.006
[download]

But...

(1.99++) ++ = 3
(1.79++) ++ = 1.9
(1.009999++) ++ = 1.02
[download]

--
Tommy
Too stupid to live.
Too stubborn to die.

That seems to be the desired behaviour. Since the numbe of decimal palces changes, I'd say that seems to be what is required.

Would be simple enough to make a function to add a specific number to the "end".

--
Steve Marvell