Revised: using %g doesn't work as expected
Round, then format. Here, I use sprintf with "%.5f" to round to five decimal places, and then use your "%7.5f" to format it. 
print "print an example of negative zero\n";
my @range = (-0.0000001, -0.000001, -0.00001, -0.0001);

foreach my $example (@range)
{
    my $twice = sprintf "%.5f", $example;
    my $tret = sprintf("rounded float:%7.5f, other:%7.5e",$twice,$twic
+e);
    
    print "The Number $example is represented as $tret\n";
}

[download]
Output: 
print an example of negative zero
The Number -1e-007 is represented as rounded float:0.00000, other:0.00
+000e+000
The Number -1e-006 is represented as rounded float:0.00000, other:0.00
+000e+000
The Number -1e-005 is represented as rounded float:-0.00001, other:-1.
+00000e-005
The Number -0.0001 is represented as rounded float:-0.00010, other:-1.
+00000e-004

[download]
Caution: Contents may have been coded under pressure.

In reply to Re: Negative zero? There's gotta be a sprintf that undoes that, right? by Roy Johnson
in thread Negative zero? There's gotta be a sprintf that undoes that, right? by rgiskard

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