How to adjust x-axis in a plot?

Hi,

I am trying to plot a global picture (as shown in figure attached) where my x-axis is from 180 to -180 longitudes but I need to adjust it to start from 0 longitudes and and end with just before 0 longitudes (a sample is also shown).

Please suggest how to achieve that?

Main Figure:

How I want:

Answer 1

[ANKUR KUMAR]

You can use circshift to rotate your data in a circular fashion. Once you have the circular shifted data, you can just manipulate the coastlon to get the longitudenal range starting from 0 to 360.

Here is an example using reanalysis data.

clc
clear
file='gdas.txt';  % this is really a netcdf data, 
% %but I have changed just the file extension to attach this file here in the answers


lon=ncread(file,'lon');
lat=ncread(file,'lat');
tmp=ncread(file,'tmp');

load coastlines

figure

contourf(lon, lat, tmp', 'linecolor','none')
hold on
plot(coastlon, coastlat, 'k-','LineWidth',0.2)
caxis([200 320])
colormap(jet(12))
daspect(ones(1,3))
xlim([-180 180])
colorbar

coastlon=mod(coastlon,360); 
coastlon(abs(diff(coastlon))>100)=nan;  % commenting this line results into mutiple 
% horizontal lines in the plot 

figure
contourf(lon, lat, circshift(tmp,size(lon,1)/2,1)', 'linecolor','none')
hold on
plot(coastlon-180, coastlat, 'k-','LineWidth',0.2)
index=sum(lon==get(gca, 'XTick'),2);
xticklabels(lon(logical(index))+180) 
caxis([200 320])
colormap(jet(12))
daspect(ones(1,3))
colorbar

[UTKARSH VERMA]

Hi Ankur,

Thanks for helping, I have done it manually but your code seems more convinient and general method to use to get these type of results.

Answer 2

[KSSV]

To limit axes read about xlim, ylim, axis.

To put up your required lables on the axis read about xticklabel and yticklabel.

[UTKARSH VERMA]

Hi, thanks for replying.

I have read all the documents you have mentioned but, I didn't find the solution also I tried rearranging the longitudes where it starts from 0 longitude and end with 0 but it's showing following error:

Error using contourf (line 57)

Vector X must be strictly increasing or strictly decreasing with no repeated values.

The above error is because my data longitude values starts from -180 to 180.

Answer 3

[Steven Lord]

Since you're working with map data, you may want to explore the map axes that is part of Mapping Toolbox if this toolbox is available to you. There are a number of properties of map axes that you can control (including projection as well as longitude and latitude limits) that may be of use to you in creating this map graphic.

[UTKARSH VERMA]

Hi Steven,

Thanks for your suggestion, I will explore map axes.