Hi there, I am new to Julia, trying to transfer all I do from MATLAB to Julia. I have a bunch of matrices of numerical data (say 100x30). In order to keep track of what each column is representing, I defined different variables (say flows) whose values were the associated column number in MATLAB. Now I can use data(:,flows) instead of data(:,X), so I don't need to worry about the column orders and numbers every time I need to use the data. In order to avoid mistakes I was using "struct" in MATLAB to avoid introducing many new variables into each code that I have. Then all those constant values (column numbers) were defined in a function (say myconstants) and when I needed to use them, I would just say C = myconstants, and then use C.flow for the column number. The problem is that there are a few categories of these constants, and they all have subfields with meaningful names and values representing the column number in each matrix of data. In MATLAB all I needed to define these was for example, C.flows.out = 5.
I am now thinking of the best way to handle this in Julia. I have learnt a bit about immutable composite types. But first, because they do not accept default values, the code will be very messy with a lot of different fields. I am also not sure if you can define the fields of an immutable to be an immutable type itself. Is that possible? Any ideas on better ways to handle this situation? In addition, if I use composite types it seems that I am using a very powerful thing (composite types) for a very basic application! Any thoughts are greatly appreciated. Thanks, Pooya
