matlab refuses to import large .mat files

When I try importing mat files saved using the -v7.3 format,(using the command below):

save('myfile.mat','-v7.3','mydata');

matlab just sits there and doesn't import them.

Any good reason for this? Makes no sense to me that it can save them but cannot import them back in.

This is extremely irritating as I am working with very large datasets, I am then having to create the data sets from scratch again by importing other data, or else split it up and save it as lots of separate mat files.

Many thanks in advance

Regards R

[Stephen23]

Use matfile.