Incidence matrix

Okay kiddo, so imagine you have a big map with a bunch of points and lines. The points are like cities, and the lines are like roads that connect them.

Now, let's say we want to keep track of which roads go between which cities. We could draw a big table and write down all the roads and which cities they connect, but that would take a lot of time and paper.

That's where the incidence matrix comes in! It's like a special table that shows which roads connect to which cities, and we can make it really quickly by drawing a bunch of little boxes.

First, we draw a box for each city and each road. Then, we put a 1 in the box where the road connects to the city, and a 0 in all the other boxes.

So if we have a city called A and a road that goes from A to B, we would draw two boxes (one for A and one for the road) and put a 1 in the box where the road connects to A, and another 1 in the box where the road connects to B.

That way, if we look at the incidence matrix, we can see which roads go between which cities really quickly, without having to search through a big table or map.

Pretty cool, huh?