Trying to find which lines are parallel

[jacob.small]

Please refrain from duplicating topics. Closing this one as the other already has replies in it.

How to find lines which are parallel to one another

Here I have a list of lines and I am trying to loop through each of them and extract parallel ones. (check each line against one another). The second step is to then put these parallel lines into separate list and check if these intersect at more than 2 points (overlap). if yes then put them in a separate list. Can anyone provide me with guidance on how to approach this. I believe the first step of checking parallelism is the most confusing. [parallel]