How do I extract data from a structure using a for loop?

I have a data structure containing 10 fields. Within each of these fields, there is another field of data that I would like to extract. Using a for loop, how do I extract the final field from each of the 10 fields in the structure? Hope that makes sense :)

[Stephen23]

"how do I extract the final field from each of the 10 fields in the structure?"

Although they can be sorted in whatever order you want, the order of fields is not something that you usually want to rely upon.

It sounds like you should really flatten your data e.g. by using one non-scalar structure. Then you could probably significantly simplify accessing your data:

https://www.mathworks.com/matlabcentral/discussions/tips/847976-tutorial-comma-separated-lists-and-how-to-use-them

Answer 1

[Image Analyst]

Not really. Fields are not ordered by number. They have names. What is the name of the "final" field in the 10 upper level fields? Is it the same name in all 10 upper level fields? What are the names of the 10 upper level fields? In general it might be something like this

thisVec = str.field1.deepField;
vec(1) = thisVec(end);
thisVec = str.field2.deepField;
vec(2) = thisVec(end);

and so on for fields 3 through 10. For only 10 I'd recommend you just put in these 20 lines rather than use a for loop where you need to use dynamic field names to access the fields.

If you have any more questions, then attach your data in a .mat file, and code to read it in, with the paperclip icon after you read this:

TUTORIAL: How to ask a question (on Answers) and get a fast answer

Answer 2

[Walter Roberson]

fieldnames = fieldnames(YourDataStructure);
num_fields = length(fieldnames);
last_field_values = cell(num_fields,1);

for FI = 1 : num_fields
    current_field = fieldnames{FI};
    subfieldnames = fieldnames(YourDataStructure.(current_field));
    lastfield_name = subfieldnames{end};
    last_field_values{FI} = YourDataStructure.(current_field).(lastfield_name);
end