A function giving the absolute value of its argument.
X = ABS(deficit) length = ABS(X1-X2)
This function converts negative numbers into positive ones. It can be used to give the difference between two numbers without regard to the sign of the answer.
It is particularly useful when you want to know the difference between two values, but you don't know which is the larger. For instance, if X=6 and Y=10 then the following examples would give the same result.
difference = ABS(X-Y) difference = ABS(Y-X)
You can use this function to check that a calculated answer is within certain limits of a specified value. For example, suppose you wanted to check that 'answer' was equal to 'ideal' plus or minus (up to) 0.5. One way would be:
IF answer>ideal-0.5 AND answer<ideal+0.5 THEN...
However, the following example would be a more elegant solution.
IF ABS(answer-ideal)<0.5 THEN....