I need to create a vector of indices for x and y coordinates and save with assigned value

I need to create a vector of indices that labels each point, for example point with index 1 that has x and y coordinates x(1), y(1) and save it into a vector such as points_index

x = [1.22, 2.33, 4.56]

y = [5.6, 7.3, 8.2]

points_index = [1 2 3]

any help is much appreciated thank you

[Wan Ji]

Is it like this?

x = ...; % your x coordinate
y = ...; % your y coordinate
points_index = 1:1:numel(x);

?

[Angela Puccini]

I dont think I explained it very well, it should be

I need to create a vector (points_index) that labels each point starting at 1 and going through to n, with coordinates x and y. For point 1 in the points_index would have coordinates x(1), y(1), point 2 would have coordinates x(2), y(2) using Matlab

x = [1.22, 2.33, 4.56]

y = [5.6, 7.3, 8.2]

points_index = [1 2 3]

when I look up point 1 in the command window it should bring up the x and y coordinate

[Wan Ji]

I dont think I catch your idea. What is called 'look up', why not use x(i), y(i) to search the points you want?

Answer 1

[Chunru]

x = [1.22, 2.33, 4.56];
y = [5.6, 7.3, 8.2];
for i=1:length(x)
    points(i).x = x(i);
    points(i).y = y(i);
end
points(2)

ans = struct with fields:
    x: 2.3300
    y: 7.3000

[Angela Puccini]

hello Chunru

when I used your code this is the message I received

Unable to perform assignment because dot indexing is not supported for variables of

this type.

Error in compute_distance (line 15)

points_index(i).x = x(i);

[Chunru]

You need to clear the variables first:

clear points_index

[Angela Puccini]

Thank you!! you are amazing!

how would I now save the points to a vector

v = [1 2 3]

[Chunru]

Please elabrate in more details what you want to do.

[Wan Ji]

I didn't know what the questioner thought, neither did you.

[Angela Puccini]

my mistake, I am confusing myself!

Thank you both for your help