ABS(num-dur)
num-dur: A number value or duration value.
The result returned by ABS is either a positive number value, positive duration value, or 0.
Examples
=ABS(A1) returns 5, if cell A1 contains 5.
=ABS(8-5) returns 3.
=ABS(5-8) returns 3.
=ABS(0) returns 0.
=ABS(B1) returns 0, if cell B1 is empty.