saving variable with -v7.3 flag check

Hi i have a code in which i have a an array with 4 field called Data

Data.name Data.index Data.PixelInd Data.bbox

I save it in the end but for some images this variable Data become large and matlab does not allow to save it as a mat File unless you turn on the v-7.3 switch.So i want to have a check in my code that if the variable is bigger than this size then save it with -v7.3 flag else save it using without this flag.

if(Data is greater than 2Gb)
save(fileName.mat, 'Data' ,'-v7.3')
else
save(fileName.mat, 'Data')
end

Thanks anyways

Answer 1

[Philip Borghesani]

Use the whos function:

varinfo=whos('data');
saveopt='';
if varinfo.bytes >= 2^31
  saveopt='-v7.3';
end
save('filename','data',saveopt);

This code is a bit too conservative in that it will use -v7.3 format when data is over 2gb but only needs to when a member of data is over 2gb. I do not see that as a problem and checking all members is a bit more work.

That said I would not do this. I would use the -v7.3 option for all files. Some day in the future it may complicate things to have files that are of different formats.