Everything is clear. Pay more attention I guess. They are different Matrix types and approaches. So, Adjacent matrix is one way to implement and incidence matrix the other.
I found the adjacency list and the adjacency matrix are so confusing. At 1:27 he says the a-b-c graph turning into Node1: Node2, Node 3; Node 2: Node1; Node3: Node3. How does that happen?? By the way, at 1:44 shouldn't it be a "{" instead of a "["??
I found this really good for understanding graph fast(before an exam). If I may suggest an improvement, it would be to cut out in the video editing the pause between definitions. Thanks for sharing!
Incidence Matrix Directed Graph He states: -1 = Leaving Node +1 = Entering Node But the graph seems wrong because the -1 and +1 are switched. Am I the only one who thinks this ?
Alberto Perez yeah actually this video has more than a few errors in it. You should get correct info on graphs elsewhere, but it's just an intro anyway.
Graphs also have the property of scale. Nodes of distances, edges, on, say, a road map, are to scale. The graph of a road map is scaled. Alternatively, a graph of, say, times of various methods of completing a process, are not to scale. Changes of the values of the an edge on a scale graph affect other edges. Not so on a non-scale graph.
Would have been much nicer if the JS examples were actually matching the picture on top, particularly with the A-B-C example, which they were most definitely NOT doing all the time - it ended up being more confusing, for no reason.
Hi Beau, thanks for the video. I think is great. Correct me if I'm wrong but it seems the js implementation of the adjacency matrix (2:25) is different from the adjacency matrix beign discussed (2:14). I may be worng as I have no experience with graphs and js.
Sigh... So many mistakes in this video. It's difficult enough to be learning/relearning things without having poor examples. I know you guys can do better than this. May I consider reuploading the video with all of your mistakes fixed?
The JavaScript code for the Adjacency List should be: var undirectedG = { a: ["b"], b: ["a", "c"], c: ["b"] }; and var undirectedGArr = [ ["b"], ["a", "c"], ["b"] ]; In the examples of code that show arrays you also forgot to change the closing bracket to a square bracket instead of a brace. I think you should consider taking down this video and uploading a new one that is correct. It is poor conduct to spread false knowledge. People who are newer to programming might become very frustrated by these examples.
1:25 - why Node3: Node3 ??? it should be Node3:Node2 !!! Node1 - is b, connected a node 2 and c node 3 node2, wwhich is a, connected to node1, i agree. but last line??? or i dont understand it???
at 4:07 he says use -1 for an edge leaving a node and 1 for entering a node. But the diagram is the opposite. So I'm confused now. Going back geekforgeeks
What a bad teacher! A person who thinks people will look at the pic of matrix and understand everything. Had that been the case, why are you speaking man? Try to explain things written on the slides.
Feedback: would be great If you could first understand the subject, then explain it. Reading the definition from e.g. Wikipedia isn't useful to anyone. Anyway thanks.
Graph representation uses nodes "a", "b", "c", and adjacency list uses nodes "1", "2", "3" : Confusing
replay video again...
Everything is clear. Pay more attention I guess. They are different Matrix types and approaches. So, Adjacent matrix is one way to implement and incidence matrix the other.
@@cenkercanbulut3069 You are talking about approaches 2 and 3 whereas he's talking about approach 1. And yes, it's a bit confusing, but not that much.
I found the adjacency list and the adjacency matrix are so confusing. At 1:27 he says the a-b-c graph turning into Node1: Node2, Node 3; Node 2: Node1; Node3: Node3. How does that happen??
By the way, at 1:44 shouldn't it be a "{" instead of a "["??
On the adjacency matrix, it should be represented as a two dimensional array.
The syntax error is not the opening [, it is the closing curly brace.
i found this confusing as well
If your examples contain a, b and c why not have the nodes contain these values. That would make this so much more clear...
I found this really good for understanding graph fast(before an exam). If I may suggest an improvement, it would be to cut out in the video editing the pause between definitions. Thanks for sharing!
Incidence Matrix
Directed Graph
He states:
-1 = Leaving Node
+1 = Entering Node
But the graph seems wrong because the -1 and +1 are switched. Am I the only one who thinks this ?
Alberto Perez yeah actually this video has more than a few errors in it. You should get correct info on graphs elsewhere, but it's just an intro anyway.
I'm so happy when he said "here's how to represent them in javascript" 😄
javascript ftw
Graphs also have the property of scale. Nodes of distances, edges, on, say, a road map, are to scale. The graph of a road map is scaled. Alternatively, a graph of, say, times of various methods of completing a process, are not to scale. Changes of the values of the an edge on a scale graph affect other edges. Not so on a non-scale graph.
Thank you so much for the excellent tutorial Beau, this helped me out a lot!
Would have been much nicer if the JS examples were actually matching the picture on top, particularly with the A-B-C example, which they were most definitely NOT doing all the time - it ended up being more confusing, for no reason.
adjancey list was confusing. you used a b c, and then used node1 node2 node3...
guess all the graphs are like that.... you should make a redo
(B)Node 1: Node 2, Node 3
(A)Node 2: Node 1
(C)Node 3: Node 3
I think it's supposed to be
(B)Node 1: Node 2, Node 3
(A)Node 2: Node 1
(C)Node 3: Node 1
This is a very confusing explanation.
An amazing explanation to people who are begging to learn
Hi Beau, thanks for the video. I think is great.
Correct me if I'm wrong but it seems the js implementation of the adjacency matrix (2:25) is different from the adjacency matrix beign discussed (2:14).
I may be worng as I have no experience with graphs and js.
Woops! Your right, the ones and zeros were supposed to be in the same places.
Thanks, I'm looking forward to the next one.
I think it's a mistake, indeed
This is about on par with anything from free code camp. Living up to your reputation.
The explanation is very clear and easy to understand！
AdjMat in second example starts with a "[" and ends with a "}".
I noticed that too :)
Thank you for this amazing video.
We will be more pleased if you make it more clear and understandable.
Sweet graph I needed this video could you do more on graphs
Thanks! It is useful, cuz I am afraid I did not know about incidence matrix.
Sigh... So many mistakes in this video. It's difficult enough to be learning/relearning things without having poor examples. I know you guys can do better than this. May I consider reuploading the video with all of your mistakes fixed?
Absolutely confusing !!!!!!! ... author uses a, b and c and then uses 1, 2 and 3. Moreover the first part of the video is inaccurate as well ....
The JavaScript code for the Adjacency List should be:
var undirectedG = {
a: ["b"],
b: ["a", "c"],
c: ["b"]
};
and
var undirectedGArr = [
["b"],
["a", "c"],
["b"]
];
In the examples of code that show arrays you also forgot to change the closing bracket to a square bracket instead of a brace. I think you should consider taking down this video and uploading a new one that is correct. It is poor conduct to spread false knowledge. People who are newer to programming might become very frustrated by these examples.
thanks for the code
1:25 - why Node3: Node3 ???
it should be Node3:Node2 !!!
Node1 - is b, connected a node 2 and c node 3
node2, wwhich is a, connected to node1, i agree.
but last line??? or i dont understand it???
4:52 - parenthesis incorrect
Where is his next video on traversal ??
Thank you i understood everything very clearly :)
at 4:07 he says use -1 for an edge leaving a node and 1 for entering a node. But the diagram is the opposite. So I'm confused now. Going back geekforgeeks
Yeah I noticed this too, was looking for a comment to confirm.
Beau, why are they ones and zeros? Can it be done with booleans? To me, that makes for better semantic representational value.
It could be done with booleans but numbers allow you to have weighted edges for some of the types of graphs.
Thanks sir!
This is why you can't trust every video
Beau, what program do you use to record your screen with?
Quicktime. It came with my mac. I also used Quicktime to record the video of me.
ı love you so much
Use your code for good, makes me want to use it for evil. :P
who even uses JavaScript as example code for this?
So damn confusing. Just stick to a,b,c
This video is full of mistakes, don't trust it.
Bsdk
What a bad teacher! A person who thinks people will look at the pic of matrix and understand everything. Had that been the case, why are you speaking man? Try to explain things written on the slides.
I can build anything, i don't need stupid algorithm
too much facial expressions, not natural.
He is just reading what it appears on the screen...lol
our RAM is drained
Feedback: would be great If you could first understand the subject, then explain it. Reading the definition from e.g. Wikipedia isn't useful to anyone. Anyway thanks.
Is there a specific part where my explanation was unclear? I'd love some specific feedback and I can clarify in my graphs part 2 video. Thanks!