Rounding with sprintf and -0

johnfl68 has asked for the wisdom of the Perl Monks concerning the following question:

Hello:

I am using sprintf to round temperatures.

my $temperature = sprintf("%.0f", $temperature);

Nothing fancy, and it works fine for what I want, with one exception.

If the temperature is greater than -0.50 but less than 0.00, using sprintf gives -0, but I want just 0.

Right now I just added a if/then to change -0 to 0, but is there a simpler way?

So far in looking I have not found anything, but then some of you know some little tricks, so I figure it doesn't hurt to ask.

Thanks!

John

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Re: Rounding with sprintf and -0 by Loops (Curate) on Apr 07, 2013 at 02:04 UTC
Maybe this works for ya: `use feature 'say'; say int(-0.2 + 0.5); # 0 say int(3.49 + 0.5); # 3 say int(3.50 + 0.5); # 4` [download] Check out this thread for lots of options: How do I round a number?.	[reply] [d/l]
Re: Rounding with sprintf and -0 by Anonymous Monk on Apr 07, 2013 at 01:41 UTC
but is there a simpler way? http://stackoverflow.com/questions/6925358/sprintf-adds-minus-sign-to-zero-after-rounding/6925396 `die 0 + sprintf '%.0f', -0.5 __END__ 0 at - line 1.` [download] Signed zero in IEEE 754, Is this odd behavior a floating point problem?	[reply] [d/l]
Re^2: Rounding with sprintf and -0 by johnfl68 (Scribe) on Apr 07, 2013 at 03:03 UTC
Hmmm - I replied to this earlier, but now it is gone? To Anonymous Monk - Thank you! As soon as I read add +0 it made total sense. John	[reply]
Re: Rounding with sprintf and -0 by Khen1950fx (Canon) on Apr 07, 2013 at 06:55 UTC
Since you just want an unsigned 0, use `%u` and String::Sprintf: `#!/usr/bin/perl -l use strict; use warnings; use String::Sprintf; my $formatter = String::Sprintf->formatter( F => sub { my($width, $value, $values, $letter) = @_; my $s = sprintf "%${'width'}f", $value; $s =~ s/\.?0*$//; return $s; } ); print $formatter->sprintf( "%u", -0.5 );` [download]	[reply] [d/l] [select]
Re^2: Rounding with sprintf and -0 by Anonymous Monk on Apr 07, 2013 at 07:17 UTC
and String::Sprintf: No Khen1950fx , even sprintf has %u, not that you need to sprintf twice	[reply]