Here shown all round-like functions which exists in perl:

#!/usr/bin/perl
use POSIX;
@a=(3.3, 3.5, 3.7, -3.3, -3.5, -3.7, 3.45);
print "number\tint\tprintf\tfloor\tceil\n";
printf "%.2f\t%.1f\t%.1f\t%.2f\t%.2f\n",
    $_,
    int,
    $_,
    floor($_),
    ceil($_)
foreach (@a);
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This code produce this output:

number	int	printf	floor	ceil
3.30	3.0	3.3	3.00	4.00
3.50	3.0	3.5	3.00	4.00
3.70	3.0	3.7	3.00	4.00
-3.30	-3.0	-3.3	-4.00	-3.00
-3.50	-3.0	-3.5	-4.00	-3.00
-3.70	-3.0	-3.7	-4.00	-3.00
3.45	3.0	3.5	3.00	4.00