Need help with automated data visualization

I am designing an automated data visualization algorithm. A user uploads a collection of 100 points as x-y pairs. I want to create an algorithm to show the user a scatter plot that just plots the points or to show the user the points connected by a straight or curved line. The user wants to compare the data in the best visual way possible. Communicate (in any combination of words, pictures, pseudocode or actual code) a method to determine which type of visualization to use.