2 views (last 30 days)
Show older comments
Mark on 22 Nov 2022
-
-
Link
Direct link to this question
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates
Commented: Mark on 22 Nov 2022
Accepted Answer: Matt J
I am working with 3D gridded data with a dimension of (Longitude,Latitude,Height) and size (73x37x41). I want to plot temperature vs longitude at a slice of latitude = 0 degree and Height at 100 km and also temperature vs latitude at a slice of longitude = 0 degrees and height = 100 km.The original data does not provide data at these specific point i.e ( latitude = 0 and height = 100 km and longitude= 0 degree and height = 100 km). I know I have to interpolate my data to plot at these specific point but I am having problem in interpolating.
My data is something like this
[Long,Lat,Height] = ndgrid(0:5:360,-90:5:90,0:15:600);
Temp = rand(73,37,41)*1000;
0 Comments Show -2 older commentsHide -2 older comments
Show -2 older commentsHide -2 older comments
Sign in to comment.
Sign in to answer this question.
Accepted Answer
Matt J on 22 Nov 2022
Edited: Matt J on 22 Nov 2022
Open in MATLAB Online
[Long,Lat,Height] = deal(0:5:360,-90:5:90,0:15:600); %Fake data
Temp = rand(73,37,41)*1000;
LUT=griddedInterpolant({Long,Lat,Height}, Temp); %interpolation object
TempvLong=LUT({0,Long,100}); %slices
TempvLat=LUT({Lat,0,100});
figure(1)
plot(Long(:),TempvLong(:));
xlabel 'Longitude'; ylabel 'Temperature'
figure(2);
plot(Lat(:),TempvLat(:));
xlabel 'Latitude'; ylabel 'Temperature'
6 Comments Show 4 older commentsHide 4 older comments
Show 4 older commentsHide 4 older comments
Mark on 22 Nov 2022
Direct link to this comment
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates#comment_2477933
Thanks again @Matt J
Mark on 22 Nov 2022
Direct link to this comment
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates#comment_2477938
Hi Matt, the plots remain same if I try to plot at two different (Height = 100 km and 500 km. Like the plots for Long(:) vs TempvLong=LUT({0,Long,100}); and Long(:) vs TempvLong=LUT({0,Long,500} is same which is not realistic from the data. Can you check why this is happening.
Matt J on 22 Nov 2022
Direct link to this comment
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates#comment_2477948
Open in MATLAB Online
I don't see it in my test below:
[Long,Lat,Height] = deal(0:5:360,-90:5:90,0:15:600); %Fake data
Temp = rand(73,37,41)*1000;
LUT=griddedInterpolant({Long,Lat,Height}, Temp); %interpolation object
tiledlayout(1,2)
nexttile
TempvLong=LUT({0,Long,100}); %slices
plot(Long(:),TempvLong(:));
xlabel 'Longitude'; ylabel 'Temperature'
nexttile
TempvLong=LUT({0,Long,500}); %slices
plot(Long(:),TempvLong(:));
xlabel 'Longitude'; ylabel 'Temperature'
Mark on 22 Nov 2022
Direct link to this comment
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates#comment_2478268
Edited: Matt J on 22 Nov 2022
Open in MATLAB Online
Hi @Matt J,
From my actual data the two plots are same at two different heights. I am uploading the link for my data:
Link: shorturl.at/fghNP
My Matlab code is below:
file='data.nc';
Temp = ncread(file1,'Temperature');
Lat = ncread(file1,'Latitude')*(180/pi);% convert rad to degrees
Long = ncread(file1, 'Longitude')*(180/pi);% convert rad to degrees
Alt= ncread(file1,'Altitude');
Temp= double(Temp); %convert from single to double
Long =double(Long);
Lat = double(Lat);
Alt= double(Alt);
Long = Long(:,1,1)';
Lat = Lat(1,:,1);
Alt = Alt(1,1,:);
Alt = permute(Alt,[1 3 2]);
LUT=griddedInterpolant({Long,Lat,Alt}, Temp); %interpolation object
tiledlayout(1,2)
nexttile
TempvLong1=LUT({0,Long,100}); %slices
plot(Long1(:),TempvLong1(:));
xlabel 'Longitude'; ylabel 'Temperature'
nexttile
TempvLong2=LUT({0,Long,500}); %slices
plot(Long(:),TempvLong2(:));
xlabel 'Longitude'; ylabel 'Temperature'
Matt J on 22 Nov 2022
Direct link to this comment
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates#comment_2478513
Both 100 and 500 are well outside the range of Alt values given, and are in different units, so LUT is just doing meaningless extrapolation.
>> mnmx(Alt)
Maximum entry = 664122.1875
Minimum entry = 96420.9922
NaNs Present = NO
Mark on 22 Nov 2022
Direct link to this comment
https://jmaab.mathworks.com/matlabcentral/answers/1858918-interpolating-3d-gridded-data-at-specific-cordinates#comment_2479663
Thanks, @Matt J. I figured out where I was wrong.
Sign in to comment.
More Answers (0)
Sign in to answer this question.
See Also
Categories
SimulinkBlock and Blockset AuthoringAuthor Block Masks
Find more on Author Block Masks in Help Center and File Exchange
Tags
- interpolation
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
An Error Occurred
Unable to complete the action because of changes made to the page. Reload the page to see its updated state.
Select a Web Site
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list
Americas
- América Latina (Español)
- Canada (English)
- United States (English)
- Belgium (English)
- Denmark (English)
- Deutschland (Deutsch)
- España (Español)
- Finland (English)
- France (Français)
- Ireland (English)
- Italia (Italiano)
- Luxembourg (English)
- Netherlands (English)
- Norway (English)
- Österreich (Deutsch)
- Portugal (English)
- Sweden (English)
- Switzerland
- Deutsch
- English
- Français
- United Kingdom(English)
Asia Pacific
- Australia (English)
- India (English)
- New Zealand (English)
- 中国
- 日本Japanese (日本語)
- 한국Korean (한국어)
Contact your local office
