how to manipulate ytick?

I have plotted this graph with the following code :

plot(0:23,ozone_values(:,1),0:23,ozone_values(:,2),0:23,ozone_values(:,3),0:23,ozone_values(:,4),0:23,ozone_values(:,5),0:23,ozone_values(:,6),'LineWidth',1.3)
xlabel('Hour')
ylabel('Concentration of ozone (in ug/cm)')
title('Diurnal variation of Ozone')
legend('Jan','Feb','Mar','Apr','May','Jun')
set(gca, 'Xtick',(0:6:23))
xlim([0 23])

So my problem is that I want to change the xtick labels, given is in utc and i want to covert it in ist. For data sets i have done that part but i could not manipulate the xtick values. Those ticks will be 5:30,11:30,17:30 and 23:30 instead of 0,6,12 and 18. How can i do this particular change?

Answer 1

[Cris LaPierre]

First, let's clarify that you want to modify the xtick values, not ytick.

The best approach is to have your x values be datetimes or durations. They your xticks will be time values. You can then set the values using xtick and their appearance using xtickformat.

% Create x, y data
x = (duration(0,30,0) + hours(0:23))'; % durations - no date associated with it
y=rand(24,6);

plot(x,y,'LineWidth',1.3)
xlabel('Hour')
ylabel('Concentration of ozone (in ug/cm)')
title('Diurnal variation of Ozone')
legend('Jan','Feb','Mar','Apr','May','Jun')

% Format and place ticks as desired
xtickformat("hh:mm")
xticks(hours([5.5 11.5 17.5 23.5]))

[SWARNENDU PAL]

thank you for your answer. But 0,6,12,18 should be replaced by 5:30,11:30,17:30 and 23:30. Sorry i forget to mention that. So basically 5:30,11:30,17:30 and 23:30 these values will be overwritten. Thank you once again

[Cris LaPierre]

You have 24 data points in Y for each month. What should their corresponding x-values be (for all 24)?

[SWARNENDU PAL]

those will be hour. But in my data set those time are given in UTC time zone. So I have to shift my time as per IST time zone. So after tried many thing i have done this,the code is given below :

xticks([0 6 12 18])

xticklabels({'05:30','11:30','17:30','23:30'})

this code will replace 0,6,12,18 by 5:30,11:30,17:30,23:30.Thanks for your support sir.

[Cris LaPierre]

Ok, sorry for my misunderstanding.

Yes, changing xlabels is one way, but in this situation, I think it is better to update the underlying data and use xticks.

% Create x, y data
xUTC = hours(0:23)'; % durations - no date associated with it
xIST = xUTC + hours(5.5);
y=rand(24,6);

plot(xIST,y,'LineWidth',1.3)
xlabel('Hour')
ylabel('Concentration of ozone (in ug/cm)')
title('Diurnal variation of Ozone')
legend('Jan','Feb','Mar','Apr','May','Jun')

% Format and place ticks as desired
xtickformat("hh:mm")
xticks(xIST(1:6:end))

●

[SWARNENDU PAL]

Thank you sir.