plot a vertical line on datetime axis of a time series

Hi! I have 4 waveforms which i want to plot by using the subplot fonction. For each of them i want to plot a vertical line at a specific time. Here is my code to plot my waveform:

figure1=figure
 for k4=1
        File4=AllFiles4(k4).name;
        X4=rdmseed(strcat(P4,File4)); %('AllFiles(k).name'); 
        d9 = cat(1,X4.d);
%         dd7=d7*gainfac2;
        d10=d9/max(d9); %d2=d1/max(d1);
        d6=bandpass(d10,[0.01 50],s_rate); %d3==bandpass(d2,[4 50],s_rate)%
        ndp=length(d10);   %ndp=length(d3); 
        t=[0:dt:(ndp-1)/s_rate];
        dt2=datetime(2021,07,09,16,32,t);
%         ndp2=length(d6);
        subplot(4,1,1);
        plot(dt2,d10) %plot(dt2,d4)
        ylabel('Amplitude (counts)')
        xlabel('time (hh:mn:ss)')
        title('Waveform Geophone / Jul21')
%        hold on  
%         tMark = datetime(16,32,41);
% % %          plot([tMark tMark], 'color', 'r', 'LineWidth', 1);
%         plot([tMark tMark], ylim, 'color', 'r', 'LineWidth', 1);
% 
%          hold off
 end

when i uncomment the line that i wrote for the plot of this verical line, which are the following lines

hold on  
        tMark = datetime(16,32,41);
% %          plot([tMark tMark], 'color', 'r', 'LineWidth', 1);
        plot([tMark tMark], ylim, 'color', 'r', 'LineWidth', 1);

         hold off

i got the this as plot:

can someone help me on this? i want to plot this red vertical line in each of the waveform (here was for the plot in subplot (4,1,1) at the time position 16:32:41.

Answer 1

[Star Strider]

Perhaps —

dt = 1E-2;                                                              % Create Data
ndp = 1E+4;                                                             % Create Data
s_rate = 100;                                                           % Create Data
t=[0:dt:(ndp-1)/s_rate];
        dt2=datetime(2021,07,09,16,32,t);
        d10 = randn(size(dt2)) .* sin(2*pi*second(dt2)/10)              % Create Data

d10 = 1×10000

0 0.0062 -0.0097 -0.0005 -0.0271 0.0470 -0.0070 -0.0686 0.0394 0.0231 -0.0156 0.1088 0.0669 -0.1076 -0.1584 -0.0003 -0.0709 -0.0595 0.0506 0.2162 0.1106 0.2599 -0.0571 0.1223 0.2426 -0.1198 0.0553 0.0449 -0.1739 0.0711

%         ndp2=length(d6);
        subplot(4,1,1);
        hold on
        plot(dt2,d10) %plot(dt2,d4)
        ylabel('Amplitude (counts)')
        xlabel('time (hh:mn:ss)')
        title('Waveform Geophone / Jul21')

tMark = datetime(2021,07,09,16,32,41);
plot([tMark tMark], ylim, 'color', 'r', 'LineWidth', 1);
hold off

You need to define the date as well as the time in ‘tMark’.

To plot it, use the hold function. Another option is xline.

.

[Paul Barrette]

Thank you, Star Strider. That was helpful to me.

[Star Strider]

@Paul Barrette —

My pleasure!

A Vote would be appreciated!

[Paul Barrette]

Certainly. But how do I do that? (Sorry, am a beginner).

[Star Strider]

Thank you!

At the top of the Answer window on the right there are a number of options: Vote, Link, etc. Clicking on Vote should work.