$ perl -v
This is perl, v5.8.8 built for x86_64-linux-gnu-thread-multi
$ perl -e 'printf "%.2f\n%.2f\n", 0.335, 1.335;'
0.34
1.33
and
C:\>perl -v
This is perl, v5.8.9 built for MSWin32-x86-multi-thread
(with 9 registered patches, see perl -V for more detail)
C:\>perl -e "printf qq{%.2f\n%.2f\n}, 0.335, 1.335;"
0.34
1.34
Am I missing something (as usual)?
Update: Following ikegami's suggestion, I tried increasing the precision to 40 digits, and got:
$ perl -v
This is perl, v5.8.8 built for x86_64-linux-gnu-thread-multi
$ perl -e 'printf "%.40f\n%.40f\n", 0.335, 1.335;'
0.3350000000000000199840144432528177276254
1.3349999999999999644728632119949907064438
C:\>perl -v
This is perl, v5.8.9 built for MSWin32-x86-multi-thread
(with 9 registered patches, see perl -V for more detail)
C:\>perl -e "printf qq{%.40f\n%.40f\n}, 0.335, 1.335;"
0.3350000000000000200000000000000000000000
1.3350000000000000000000000000000000000000
It looks like this variation is just an artifact of 64-bit vs. 32-bit, emphasizing how you should never rely on precise results from rounding. |