In the chapter open-vs-closed, when the start node is visited multiple times the walk is wrongly shown to be a path/cycle.

Clicking on Show solution in Graphic Sequence unit throws bunch of Exceptions.

chrome 115.0.5790.102 64bit

it might be nice to show the symbols used in the graphic inline with the text. you could think of this as a legend, but in context, right next to the text.

I made a quick design of what this page could look like, with the symbols inline:

When I hold ctrl and try to drag a node, nothing happens.

Should be:

 colors: [6, 8, 1, 4, 8, 4], 

I feel like mathematical conventions are not so useful for programming. Maybe provide some API that can be more useful for practical tasks around graphs, or at least show how this math looks like in code. For example:

• order - graph.nodes.len
• size - graph.edges.len

• degree - node.edges.len
• minimum degree - min([n.edges.len for n in graph.nodes])
• maximum degree - max([n.edges.len for n in graph.nodes])

• degree sequence - sorted([n.edges.len for n in graph.nodes], reverse=True)
• sum of vertices degree is twice the size of graph - graph.edges.len*2 == sum([n.edges.len for n in graph.nodes])

The year for copyright is given as 2017-19 in the License section in the README. Shouldn't this be updated to 2017-20?

https://github.com/mrpandey/d3graphTheory/blob/master/README.md#license

Please check it once the text and visualizer are contradicting each other thank you.

Though "Dot"+"Edge" and RAND Node-Link are usable, it is better to describe graph systems as "Concepts related to Concepts by Concepts" where all structured knowledge and all structured associative knowledge is abstracted (as is type "class" representations of the knowledge)

Hi, first off thanks for making this, it's very cool :)

I had a lot of difficulty with the UI during the course, and I thought you might want to hear about some ideas to improve. I'm not sure if your goal for this project is to teach as many people as possible, or just to play around with D3 but if the goal is to teach, then I think fixing the below issues would help reach a wider audience.

1. Clicking on graph edges is very difficult because they are so thin. It requires a precise motion that is hard on a trackpad and hard for people that don't use computers all the time. It's very frustrating if you click near an edge, and instead it just creates a new vertex that you don't want.

2. It's preferable to not require right-clicking in an interface. I know my parents who are an 'average Joe' user don't understand what right clicking is and would be unable to do the course for that reason. Better would be either a "trashcan" area where you can drag a node that you don't want, or clicking a node to select it and then pressing a key like X to delete it.

3. On the challenges, when you complete one it automatically and rapidly advances to the next level. This is no good because after finishing, you want to look at your progress and understand what you made. Even worse, if you then click back to the previous level, your progress is gone so you can't review the old solution either. It should require pressing 'Next' to go to the next level, and it should store your solution in local storage or something so you can look back at it.

4. The spring layout of D3 is very distracting when it bounces around rapidly, especially at the start of a level. Could the vertices be initialized to their proper positions? Or, it would be better to hide the canvas for the first couple seconds until the nodes have settled down.

5. Because the graph is colorful and moving, it draws attention away from the text a lot, which makes it hard to read the text instead of just poking at the graph. If there's important text to read before you start playing, then the graph should only appear after the user has scrolled through the text or pressed a button at the bottom.

Hi there, I really like this project you are working on xD! I think these tutorials and the concepts breakdowns would be quite helpful for graph theory new learners.

I see you are still expanding your list, and I'm just wondering do you maybe consider adding a new topic about graph center? I think it's an really interesting and useful concept(as well as the Floyd–Warshall algo comes along w/ it), and I'd love to help contribute if you think that sounds good :)

Thanks for creating this, I like this interactive course!

There is a mistake in the proof at https://mrpandey.github.io/d3graphTheory/unit.html?pigeonhole

The argument goes like:

1. if graph has vertex with degree 0 then ..
2. if graph has vertex with degree n-1 then..

But the argument says nothing about graphs that don't have one of the vertices with such degrees.

To be correct, it should probably go something like this:

1. if graph has vertex with degree 0 then we're choosing from degrees 0 .. n-2
2. if graph doesn't have vertex with degree 0 then we're choosing from degrees 1..n-1

Hello,

Shouldn't that be

A sequence of numbers is said to be a graphic sequence if...