plotting live data in matlab

hi, i get data imported every minute via excel. I want to plot this data as realtime in a graph so it gets updates automatically. how can i do this? any ideas?

Answer 1

[Himanshu]

Hey,

To read and plot and live data from an axcel into Matlab, you can setup a loop that constantly reads from the excel and keeps updating the plot. Here is how you can do it:

1. Use a while loop to continuously check for new data.
2. Use readtable or xlsread to import data from the Excel file.
3. Refresh the plot with the new data.
4. Use pause to wait for a specific duration (e.g., 60 seconds) before checking for new data again.

Here is the sample code for the same:

% Initialize figure
figure;
hold on;

% Infinite loop to update the plot
while true
    % Read data from the Excel file
    data = readtable('yourfile.xlsx'); % Replace 'yourfile.xlsx' with your Excel file name
    
    % Extract the relevant columns for plotting (assuming 'Time' and 'Value' for now)
    timeData = data.Time;
    valueData = data.Value;
    
    % Clear the current plot
    cla;
    
    % Plot the new data
    plot(timeData, valueData, '-o');
    
    % Update plot title and labels
    title('Real-Time Data Plot');
    xlabel('Time');
    ylabel('Value');
    
    % Pause for 60 seconds before updating again
    pause(60);
end

Hope this helps!

[Walter Roberson]

Note that the cla is not needed there. Just remove the "hold on".

Unless, that is, you want to plot the cumulative data, despite the fact that the same data might be read twice (if the file does not update.) But on that case, you would remove the "cla"

There are more efficient ways to do the plotting, but the details depend on whether you want cumulative plotting or just to plot the current contents of the file.