How to plot from listbox

I need help with plotting data from a listbox. the program populates the list box from a folder containing multiple .CSV files, each file containing data. The file is then clicked on and plots a graph with the data. I cannot figure out how to plot the data. My instinct is to create a variable with the name of the file when clicked and then use csvread to extract the data and plot. What I can't figure out is how to set a variable to the clicked file in the listbox.

function homework8
f=figure;
x=linspace(0,6,10020);
a=axes('Position',[0.1300 0.1317 0.4593 0.7731])
listbox=uicontrol('style','list','position',....
    [346.3333 54.3333  135.0000  283.3334],'Callback',@plot);
btn=uicontrol('parent',f,'style','pushbutton','position',...
    [344.6667 349.6667 135.6667 30.3333],...
    'String','Select Folder','Callback',@openfolder);
%%Callbacks

function openfolder(~,~)
    folder = uigetdir();% returns the path for the directory
    files = dir(folder); % sets the directory to chosen folder
    listbox.String={files(:).name}; % puts files into listbox

end
%%plot data

     %data=% my file name I click in listbox
     y=csvread('data',18,2) %take data from file

plot(x,y)     

end

Answer 1

[Divyajyoti Nayak]

Hi Brian,

To plot data from the file selected in the list box, the name of the file needs to be extracted from the cell array in listbox.String. This can be done by using the listbox.Value property to index into the cell array.

https://www.mathworks.com/help/matlab/ref/uicontrol.html?s_tid=doc_ta#mw_0668290c-e27d-405b-81f6-7666e13363b3

Here’s some code to help:

f=figure;
x=linspace(0,6,10020);
a=axes('Position',[0.1300 0.1317 0.4593 0.7731]);
listbox=uicontrol('style','list','position',....
    [346.3333 54.3333  135.0000  283.3334]);

listbox.Callback = {@Plot, listbox, a};
btn=uicontrol('parent',f,'style','pushbutton','position',...
    [344.6667 349.6667 135.6667 30.3333],...
    'String','Select Folder','Callback',{@openfolder,listbox});
%%Callbacks

function openfolder(~,~, lb)
    folder = uigetdir();% returns the path for the directory
    files = dir(folder); % sets the directory to chosen folder
    lb.String ={files(:).name}; % puts files into listbox
end
function Plot(~,~,lb,ax)

     fileName = lb.String{lb.Value}; %Getting file name from listbox.String
     data = table2array(readtable(fileName)); %take data from file
     plot(ax,data(:,1),data(:,2));     
end