# How can I plot two different datetime vectors in the same graph?

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Ron Nativ on 9 Nov 2018
Commented: Ron Nativ on 9 Nov 2018
Hi All,
I have two datetime vectors (time1 and time2) with different sample period and different lengths.
Each of these vectors corresponds to different variable. For example - the first vector (time1) corresponds to to water velocity (V) in a river, and the second (time2) to rain intensity (R).
Since they cover the same time range (April to November, 2018) I would like to plot them on the same graph. However, I don't seem to manage doing so, probably because they differ in length and sample frequency.
Could anyone share any solution to that?
Thanks, Ron
Ron Nativ on 9 Nov 2018
Thank you all for answering, Caglar, you are right, the problem was not related to the specific graphic coding, but to my data handling. Sorry for that and thanks again!

Caglar on 9 Nov 2018
Edited: Caglar on 9 Nov 2018
Comment if any part is not clear.
first_date_array=datetime('today'):days(1):datetime('today')+days(10); %array for 10 days
first_data=1:1:11;
second_date_array=datetime('today'):days(2):datetime('today')+days(15); %array for 15 days and it has data for each 2nd day only
second_data=8:-1:1;
figure(1); %method 1: plot them together
plot(first_date_array,first_data,'o',second_date_array,second_data,'o'); %x,y,markershape,x,y,markershape
xlabel('Datetime'); ylabel('Data')
legend('First','Second')
figure(2); %method 2: add new plots using hold on
plot(first_date_array,first_data,'o');
hold on
plot(second_date_array,second_data,'o');
xlabel('Datetime'); ylabel('Data')
legend('First','Second')

madhan ravi on 9 Nov 2018
Edited: madhan ravi on 9 Nov 2018
Or try
yyaxis right
plot(time1, V)
yyaxis left
plot(time2, R)
Also notice the X axis which is not in a datetime format (although the vectors are!)
xtickformat('dd-MMM-yyyy')
An example:
t = datetime(2014,6,28) + calweeks(0:9);
y = rand(1,10);
yyaxis left
plot(t,y);
y = 1:10;
yyaxis right
plot(t,y(1:numel(t)));
AX=findall(0,'type','axes');
AX(2) %grabs second axis handle experiment and see by scrolling the graph
xtickformat(AX,'dd-MMM-yyyy')