Adjust intervals of x-axis in the plot!

Hey all,

I have SI and Date which I want to plot them. The Date is in a monthly format from 1989 to 2018 (360 months). I haven't any idea why the x interval divided into 5 years by Matlab:

But I want to set it in the monthly format.

Also, any idea how to get rid of the green line? I don't want it and I don't know why it is showing today? Yesterday I haven't this problem (the green line didn't show yesterday)

Any advice highly appreciated.

%plot vector
plot(Date,SI, 'linewidth',1.5)
xlabel('time step')
%Modify "time step"
ylabel('Precipitation')

[Rik]

Do you really want 360 tick marks?

Also, the code you showed will not result in the image you posted. You can make sure you start with a fresh figure by closing all your figures, or by using clf. I personally prefer something like the code below.

%guaranteed empty figure, with the handle stored in a variable
f=figure(1);clf(f)

[BN]

Dear Rik,

Thank you, according to your comment I used the

%guaranteed empty figure, with the handle stored in a variable
f=figure(1);clf(f)

and then use this code below:

plot(Date,SI, 'linewidth',1.5)
xlabel('time step')
%Modify "time step"
ylabel('Standardized Precipitation Index')

and here is the result:

Yes I want 360 tick mark based on for example: Jan 1989, Feb 1989, ... Dec 2018.

After that I cand make font size small and rotate tick marks.

I don't know how to do it.

Thank You

[Rik]

Even after rotating the ticks they will not be readable.

What release are you using?

[BN]

Dear Rik, I am using Matlab R2018b.

If you think the cant be readable can you do me a favor and tell me how to use yearly intervals? like 1989 - 1990- ... 2018?

Thank you

Answer 1

[Rik]

You can directly set the tick locations with the xticks function. Since your variable is already a datetime (and not datenum), you don't need the datetick function.

S=load('Date.mat');
Date=S.Date;
S=load('SI.mat');
SI=S.SI;

%since the last 11 columns of SI are empty, let's remove them
SI=SI(:,1);

f=figure(1);clf(f)
plot(Date,SI, 'linewidth',1.5)
xlabel('time step')
ylabel('Standardized Precipitation Index')
xticks(Date(1:12:end))
ax=gca;
set(ax,'XTickLabelRotation',45)

[BN]

Thank you