Correcting the label in a 3D scatter plot

Hello there,

I have a .xls file that contains x,y,z vertics. The sequence goes something like this (that header of each): x0,y0,z0,x1,y2,z2,..........x1000,y1000,z1000. (3000points in total) Each x,y,z together forms a point I see in the scatter 3D point. I am wondering how to identity/access that particular point properly, say x0,y0,z0 will be verticx 0, x1000,y1000,z1000 will be verticx 1000.

That's what I have from the help eailer:

clc;clear all;
[num,txt,raw] = xlsread('test_april24.csv');
for i = 1:3:3000
    a = num(3,i);
    b = num(3,i+1);
    c = num(3,i+2);
    k=scatter3(a,b,c, 'filled');
    S=string(1:3000).';
    text(a, b, c, S);
    row = dataTipTextRow('Index: ',i');
    k.DataTipTemplate.DataTipRows(end+1) = row;
    hold on
end

The index number is now just showing one of the axis (since its based on the total number i) say index 3000 but I am expecting 1000

In addition, when the index popped up, is there a way that I can access a participant point that I am interested? say x100,y100,z100 (verticx100)?

Many thanks!

[Image Analyst]

You forgot to attach 'test_april24.csv'. Make it easy for us to help you.

[darova]

Can't run the script

[steamrice]

I attached that and hope that I illsutated what i was trying to achieve! Thanks for your time

[steamrice]

Sorry I uploaded the .csv one now

[steamrice]

Are you able to open that? @darova

Thanks

Answer 1

[darova]

I used currentPoint property of callback to get coordinates of mouseclick

currentPoint returns 2 points in 3D space. I used crossp roduct to find closest point

See script inside

[steamrice]

Thanks for the response! I am wondering should I keep what I had or just call your function directly after my for loop? Beacause I would need to read my excel file first

[darova]

Use this function after for loop.

[steamrice]

Thanks for the response! I saw those 10 random points plotted together on my data and it pops with the corresponding vertex (vertex 1 to vertex 10). However, I am trying to acheive the proper indexing on the original data (corresponding to the excel file header)?

[darova]

I copied 3d row of excel file into text file

Put this part inside the script

a = load('data.txt');
n = fix(length(a)/3)*3;
x = a(1:3:n);
y = a(2:3:n);
z = a(3:3:n);
h = plot3(x,y,z,'.r');
axis vis3d

[steamrice]

Wow! Thats what I am trying to achieve! I am trying to replace the x,y,z =rand(10,1) with you mentioned above and it worked!

So did you just tried to copy the .csv file into a text file directly? (without the header)

[darova]

I couldn't import data from excel file. So i just saved some as txt

[steamrice]

No problem! Thanks for the suggestions here.

That's what I was trying to achieve there. If you don't mind ask a follow up question, is the vertex that I see here corresponding to the header of the excel? I am wondering is there a way for me to verifiy this? Like if click vertex 1, would it be able to show its x,y,z component so I can go back to the excel/ text file to verfiy that?

[darova]

Sure. Go inside callback function and add this line

% line(x(ix),y(ix),z(ix),'marker','*')
[x(ix) y(ix) z(ix)]

Answer 2

[Image Analyst]

If you want vertex 100, just use that index to get the x, y, and z values:

x100 = x(100);
y100 = y(100);
z100 = z(100);

[steamrice]

Thanks for the response! I am trying that! But also the other question I had was is it possbile to show x0,y0,z0 as index 0 rather than a column number? The current situaition is that the index is only referring to one of the axises, which I will have to go back to the excel to check the column number...

[Image Analyst]

Not sure what that means. There is no row zero or index zero in a matrix. In MATLAB all matrices start with row 1 and column 1. So I assume x0,y0,z0 are all in index 1, so what's wrong with saying

x0 = x(1);
y0 = y(1);
z0 = z(1);

[steamrice]

Sorry for not being clear. I mean I would like to match the index I see in the plot to the excel header. Say x0,y0,z0, I would hope it corresponds to index 0 rather than a column number, say 5...

[Image Analyst]

Still not sure what you mean. MATLAB uses 1-based arays, not 0-based arrays like C++. See the FAQ: FAQ #22 Subscript_indices_must_either_be_real_positive_integers_or_logicals

[steamrice]

Thanks for response! I think maybe attaching an image might help here

I was testing with these two lines, txt is 1x3000 index and I tried to convert it to 3000x1 string. They are the header you'd see in the excel file ("v0_x", "v0_y", "v0_z" ..."v3000_x", "v3000_y", "v3000_z" 0

index=string(txt.');
row = dataTipTextRow('Index: ',index);

The problem I am having and wanting to achieve, as you can see in the picture, is the index is not showing it properly. The two points that I click, they both showed v0x (in fact, as of now, all points is v0x becase of the above code). I want to have the index properly corresponds to its x,y,z component (matching the excel file).

[steamrice]

Does that mean more sense.. Thanks!

[Image Analyst]

No, but it looks like darova figured out what you want and solved it because you accepted his/her answer.