Option 1: Check, no repetitive x value
option 2: Check the x are not repetetive and make a gradually reasonable function
Option 3: dont check it. It has repetitive x points.
option 4: Check, the x value isn't repetetive, and it doesn't matter if it was y that's repetetive, that means that the line is horizontal,
option 5: Dont check, repetetive x values dont make a function.
