mod

#mod

##Syntax mod

##Description The mod (modulo) operator produces the modulo of one number with another. In other words, the result is always a number between 0 and the second operand. If both operands are positive, the result is identical to the remainder operator. For example, 7 mod 2 produces 1 and 12 mod 5 produces 3.

##Example In this example, hours is the current time. It is moved back and forth by a random amount, but the final result must always be between 1 and 12 (the mod operation produces a number between 0 and 11 and then 0 becomes 12).

    var hours : int := 12
    var hoursPassed : int
    put "The time is now ", hours, " o'clock"
    loop
        randint (hoursPassed, -12, 12)
        exit when hoursPassed = 0
        if hoursPassed < 0 then 
            put hoursPassed, " hours before " ..
        else
            put hoursPassed, " hours later " ..
        end if
        put hours, " o'clock" ..
        hours := (hours + hoursPassed) mod 12
        if hours = 0 then 
            hours = 12
        end if
        put " it was ", hours, " o'clock"
    end loop

##Details If the second operand is positive, then the result is always non-negative. Likewise, if the second operand is negative, then the result is always non-positive. If both operands are negative, the result is the same as the remainder operator.

##See also infix.html operators, precedence.html of operators and the rem.html and div.html operators.