Create a graph with several isolated nodes and a few links

Why I am not able to create a graph with several isolated nodes and a few links?

s = [1
     1
     1];
t = [1
     2
     3];
XY = [    1          1.5
          1.2          1.7
          1.3          1.3
          1.7          2.2
            1            2
          4.2          2.9
          3.5          2.5
          3.8          2.9
          3.8          3.2
          3.6          3.1
            3            3
          3.4          3.4
            3          2.3];
G = graph(s,t);
G.Nodes.X = XY(:,1);  G.Nodes.Y = XY(:,2);

Error using .
To assign to or create a variable in a table, the number of rows must match the height of the table.

Error in graph/subsasgn>assignToNodes (line 161)
nodeprop = subsasgn(nodeprop, S, V);

Error in indexing (line 18)
G = assignToNodes(G, S, V);

[Dyuman Joshi]

@Sim, what exactly are you trying to do with this particular line of code?

G.Nodes.X = XY(:,1);  G.Nodes.Y = XY(:,2);

[Sim]

Hi @Dyuman Joshi! I am just trying to assign X and Y coordinates to my 13 nodes (of the graph)....

[Dyuman Joshi]

A Graph does not have any coordinates related to it. And, you have only 3 nodes not 13.

What is your purpose by trying to assign coordinates to the nodes?

[Sim]

"What is your purpose by trying to assign coordinates to the nodes?"

To show isolated nodes, i.e. without links to other nodes :-)

[Dyuman Joshi]

But there are no isolated nodes in your graph -

s = [1
     1
     1];
t = [1
     2
     3];
G = graph(s,t);
plot(G)

[Sim]

Hi @Dyuman Joshi! Thanks for your comments! I think @Steven Lord got my point..... Sorry, I think I did not explain well my issue... :-)

Answer 1

[Steven Lord]

Your code would work with one minor addition, a line that adds the additional nodes to the graph that are not present in the s and t vectors you use to create the graph.

s = [1
     1
     1];
t = [1
     2
     3];
XY = [    1          1.5
          1.2          1.7
          1.3          1.3
          1.7          2.2
            1            2
          4.2          2.9
          3.5          2.5
          3.8          2.9
          3.8          3.2
          3.6          3.1
            3            3
          3.4          3.4
            3          2.3];
G = graph(s,t);
G = addnode(G, height(XY)-numnodes(G)); % Added
G.Nodes.X = XY(:,1);
G.Nodes.Y = XY(:,2);

Let's plot the graph and see the isolated nodes.

plot(G, 'XData', G.Nodes.X, 'YData', G.Nodes.Y)

If later on you want to connect some of those isolated nodes to others, use the addedge function.

[Sim]

Thanks a lot! This is what I was looking for :-)