how to save multidimantional matrix as structure?

how to save multidimantional matrix as structure?

i get this error:

>> save('filename','H')

Index exceeds matrix dimensions.

[Adam]

How big is your matrix?

[Michael Haderlein]

Do you, by accident, have a variable called "save"?

[Kobi]

yes. thank you!

[Adam]

I was going to ask that, but I though surely no-one would call a variable 'save'!! I have fallen for that on many occasions too though with min, max and other functions like that.