How can I create multiple arrays, based on unique column values, from a single array?

I have a large array that I would like to separate into different arrays, based on the "ID" value, so I can plot Temp vs Speed for each ID.

What kind of loop would I use? I've included a sample of my data below.

ID                Speed            Temp
232459        120                80
232459        240                150
232459        100                70
217220        150                85
217220        130                82
217220        100                71
217220        101                72
217220        110                81
217220        100                74
195321        110                84

It would also be nice to have each array be named the "ID Number"

[the cyclist]

How are these data stored? Are they in a numerical array (and you simply wrote the column header here for our convenience), or are they stored in a table? Or something else?

Also, do you really need these stored when all is said and done, or could your loop be something like ...

for <each ID>
    % create temporary variables for this ID's speed and temp
    % plot a figure using that temporary variable
end

Answer 1

[David Hill]

For your array x:

function Plot(x)
hold on;
z=x(:,1);
arrayfun(@(y)plot(x(ismember(z,y),3),x(ismember(z,y),2),'Marker','*','MarkerSize',10,'LineStyle','none'),unique(z));
end

Answer 2

[Walter Roberson]

G = findgroups(YourTable.ID);
grouped_info = splitapply(@(speed, temp) {unique(id), speed, temp}, YourTable.id, YourTable.Speed, YourTable.Temp, G);

This will return a cell array of information, with 3 columns. The first column contains (one copy of) the ID that applies for the row. The second column contains the speeds that existed for that ID. The third column contains the corresponding temperatures that existed for that ID.

You could even plot fairly directly:

G = findgroups(YourTable.ID);
hold on
line_handles = splitapply(@(id, speed, temp) plot(speed, temp, 'DisplayName', unique(id)), YourTable.id, YourTable.Speed, YourTable.Temp, G);
hold off
legend show