The FLOOR function returns the largest integer that is less than or equal to the supplied number. The result is cast into a integer type in the operation.
FLOOR(number) : integer
The example query adds a calculated column with a value of 4, which is the largest integer that is less than the supplied number.
gorrow chr1,1,1 | CALC test floor(4.2)
chrom bpStart bpStop test chr1 1 1 4