What do you mean by a fixation point? Can you give us more information about what you are trying to do and specifically what data you have collected?
I had participants who were reading a paragraph on paper, screen and mobile device. I want to compare the linearity when reading from the different platforms. I used an eye tracker to record the eye movements and the data it produces is in form of fixation points x, y. Fixation points are where participants looked when reading. In the attached file, there are fixation points x, y for 2 participants. I must compare the linearity betwwen the two when they read the same paragraph.