涉及python类型更改的OOP问题的优雅解决方案

Question

I run into an OOP problem when coding something in python that I don't know how to address in an elegant solution. I have a class that represents the equation of a line ( y = mx + b ) based on the m and b parameters, called Line . Vertical lines have infinite slope, and have equation x = c , so there is another class VerticalLine which only requires a c parameter. Note that I am unable to have a Line class that is represented by two points in the xy-plane, if this were a solution I would indeed use it.

I want to be able to rotate the lines. Rotating a horizontal line by pi/2 + k*pi ( k an integer) results in a vertical line, and vice versa. So a normal Line would have to somehow be converted to a VerticalLine in-place, which is impossible in python (well, not impossible but incredibly wonky). How can I better structure my program to account for this problem?

Note that other geometric objects in the program have a rotation method that is in-place, and they are already used frequently, so if I could I would like the line rotation methods to also be in place. Indeed, this would be a trivial problem if the line rotation methods could return a new rotated Line or VerticalLine object as seen fit.

Answer 1

Geometric objects that have a fixed boundary/end-points can be translated and rotated in place. But for a line, unless you talk about a line from point A to point B with a fixed length, you are looking at both end-points either being at infinity or -infinity ( y = mx + c ). Division using infinity or -infinity is not simple math and hence I believe complicates the rotation and translation algorithms