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Perl rounder...

by abaxaba (Hermit)
on Apr 08, 2002 at 21:05 UTC ( #157555=snippet: print w/ replies, xml ) Need Help??

Description: Just a little hack to round numbers. Strips leading zeros, pads the precision of you want more places then your decimal length...

#!/usr/bin/perl

main();
sub main
{
    my ($num,$prec)=@ARGV;
    my ($mant,$dec) = split (/\./,$num);
    $dec=$dec?$dec:"0";
    $mant=~s/^(-?)0+/$1/;
    $mant=!$mant?0:$mant;
    ($prec,$dec)=$prec==0?($prec,undef):($prec+1,substr($dec,0,$prec+1
+));
    $dec=~s/$dec/length($dec)<$prec?$dec."0"x($prec-length($dec)):$dec
+/e;
    my $round = join ("",($mant,length($dec)?".":"",round($dec)));
    output ($round);
}
sub round
{
    my $dec=shift;
    $dec=~s/(\d)(\d)$/$2<5?$1:$1+1/e;
    $dec;
}

sub output
{
    print "Round = ",shift,"\n";
}

Comment on Perl rounder...
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Re: Perl rounder...
by maverick (Curate) on Apr 08, 2002 at 22:21 UTC
    Sorry dude, it's already been done.
    printf("%.$ARGV[1]f\n",$ARGV[0]);
    printf takes a sting that describes what you want to print. In your case a floating point number (f) with a precision that you specify as the second arg ($ARGV[1]) using the value in $ARGV[0]

    /\/\averick
    OmG! They killed tilly! You *bleep*!!

      Explains the negative comments votes.... REAP it then.
Re: Perl rounder...
by gav^ (Curate) on Apr 08, 2002 at 22:36 UTC

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