Answer:

Explanation:

I'm trying to write a FUNCTION that answers the QUESTION: if you start counting at a and stop counting at b, is c in that range (aka is c between a and b).

Normally a < c && c < b would suffice, but I'm in modular arithmetic:

(Diagram)

Counter-clockwise is increasing.

Green colors: are values for c where the algorithm should indicate true (where c is between a and b)

Blue colors: are values for c where the algorithm should indicate false (where c is not between a and b) (which happens to be the same as where c is between b and a)

The simple a < c && c < b fails where the range of a and b crosses over 0.

For example, say A = 300 and B = 45. If C is 10 then the function should return true: 300, 301, 302 ... 359, 0, 1, 2, 3 ... 8, 9, 10, 11, 12 ... 43, 44, 45. Therefore, 10 is between 300 and 45 in mod 360.

Ultimately, what I'm trying to determine is if ONE hue is between two other hues, where hues are specified in degrees around a color wheel (which is a mod 360 system). It would be great if the answer was in terms of mod n so it would solve the general case and not be specific to my problem though.

algorithm