Draw vertical lines on a plot

Hi,

I have a plot and I want to draw several vertical lines (about 40 of them) at specific locations on the plot. How do I go about it? Any code that I can put all those locations in and automatically mark those regions of the plot with vertical lines for me? Thanks!

Answer 1

[Luna]

There is a built-in function for that.

For vertical lines use xline and for horizonal lines use yline.

Here is sample code:

regions_to_be_marked = randn(40,1); % array of the points you want to plot vertical line (x axis values)
x_data = randn(100,1); % x data to plot
y_data = randn(100,1); % y data to plot

hFig = figure; % figure handle
hAxes = axes(hFig); % axis handle
hPlot = plot(hAxes,x_data,y_data,'LineStyle','none','Marker','*'); % your actual plot
hold on; % holds current plot

% plot each region in for loop
for i = 1:numel(regions_to_be_marked)
   xline(hAxes, regions_to_be_marked(i),'LineWidth',2,'Color','red');   
end

[Curious Mind]

Thank you!

[Luna]

Your welcome :)

Answer 2

[the cyclist]

If you have R2018b or later, you can use the xline command.

If you have an earlier version, you can use the line command (which is just a bit more working in defining the endpoints).

[Curious Mind]

Thank you for the information. I have seen the xline function but if I have say 40 regions I want to mark, I will have to do it for each one of them. Is there a way to enter all 40 regions and get those regions marked at the same time?

[Luna]

Check my answer above, I made a sample plot for your case.