Re: Using (s)printf()

[Anonymous Monk]

Your statement and example under "Rounding Numbers with sprintf()" is incorrect and misleading. Using "%d" does NOT round a float as necessary, it merely truncates everything after the decimal. Thus, printf("%d", 3.99); # will print 3, not 4.

# To properly 'round a float as necessary':
printf("%.0f", 3.49); # This will print 3
printf("%.0f", 3.51); # This will print 4

[Anonymous Monk]

Perl exhibits strange behaviour after moving from x32 to x64 platform:

Before:


# perl -e 'printf("%.2f", 6.685);'
6.68

# perl -v
This is perl, v5.10.1 (*) built for i386-linux-thread-multi

After:


# perl -e 'printf("%.2f", 6.685);'
6.69

# perl -v
This is perl, v5.10.1 (*) built for x86_64-linux-thread-multi

Any changes in rounding algorithm?

[Anonymous Monk]

Any changes in rounding algorithm?

Nope, see Is this odd behavior a floating point problem?

[Anonymous Monk]

It looks like there is a problem with numeric.c: Perl_grok_number (Perl's own string-to-number conversion).

Perl bugs tickets #115092, #41202