How to build dataset using vector and matrix and structure

I have matrix and structure datas.

I want make a dataset that have a data name, value, matrix, structure.

and How to call these data from dataset

ex. dataset.fftdata(3)-> that is matrix
    dataset.spectrum.octavedata(3)-> that is matrix data from structure data

[Honglei Chen]

Could you be more specific? This looks just like structs? Did you try it?