MATLAB: How to load a field from a saved structure

fieldloadsavestructures

For my work, it is convenient to store measurement data in structures with many fields. The structure is useful for keeping all the measurements together, passing into functions that plot everything, etc. However the files get large and bulky to handle. I'd like to be able to load a specified field from the *.mat file containing the structure. I thought this was possible using this approach (saving with -struct flag), but only separate variables containing the fields are saved and the original structure is lost. Is there a way to retrieve a field out of an existing mat file containing a structure, as is shown below, perhaps using matfile ?
% Make the structure
a.Temperature.value = rand(1,10);
a.Temperature.units = 'C';
a.Humidity.value = rand(1,10);
a.Humidity.units = '%';
save('c:\temp\junk.mat', 'a'); % Save the structure
load('c:\temp\junk.mat', 'a.Temperature'); % Load a specified field (doesn't work)

Best Answer

save('c:\temp\junk.mat', '-struct', 'a');
load('c:\temp\junk.mat', 'Temperature');
should work I think. Or
loadedVars =  load('c:\temp\junk.mat', 'Temperature');;
Temperature = loadedVars.Temperature;
if you prefer.
Related Question