Output from nested struct into numerical / string array

Hello together,

I'm a bit bothered that I dont find a way to do this in a elegant way. Lets say I receive some output from a struct like this:

mystruct.somenesting.objecttype.name
mystruct.somenesting.somethingelse.size

both will return me a list of names (char arrays) or sizes (double), but not as an array, but as 'selected' outputs (ans = ' ' , ans = '')

I can only "catch" this output into a cell array like this:

CA = {mystruct.somenesting.objecttype.name}

I would like to directly put it into a string array, or a double array without first saving it as cell array and then either transforming it (cell2string) or using a loop to go through each element and convert the elements.

It feels like I'm just missing a little trick with brackets :-/

A similar issue arises if I just want to read the contents of the cell array into a new array by trying to evaluate all cells with :

valueCA = {mystrut.some.thing.value}
valuearray = [valueCA{:}];
valuearray(:) = valueCA{:};

They're both wrong. I need the {:}, that I'm sure off, but I dont know how to read each value into another variable so it doesnt overwrite each other.

Edit:

Appended an example struct

stringarray = string({msmtrun.pipelines.name}); 

does work, I just hoped there was a smoother way to do it (without a function call)

cellarray = {msmtrun.pipelines.name};
stringarray = cellarray(:); %Not a string array

I imagine my problem lies there, that the cells are filled with char arrays, which need to be converted into a string first to build a string array.

Similarly I cant get the contents of all cells into one (1x) char array, bc that would mean loosing the seperations from the cell. And I cant get it into a multidimensional char array, bc the char arrays have different lengths.

As for the double, I think it was a bracket error, I cant reproduce it for now. If I access

msmtrun.pipelines(1,1).data(1,1).data 

I get an array of doubles as expected.

[madhan ravi]

What about

string(mystruct.somenesting.objecttype.name) %?

[Stephen23]

"...by trying to evaluate all cells ..."

Cell arrays contain data: data cannot be evaluated, only code can be evaluated. Therefore it is unclear what you actually mean. Please explain what you expect to happen.

Most useful would be a complete MWE, including all input arrays and expected output arrays. Otherwise we will just spend a lot of time guessing the classes/sized of that data (which so far you have not explained at all).

[mahoromax]

Just using

string(mystruct.somenesting.objecttype.name) %?

returns

Error using string
No constructor 'string' with matching signature found.

I apologize for my imperfect terminology. But when talking about cell's we should now that you can access the cell itself and its contents - using () vs {} brackets for example. I dont think its a faar stretch to guess that with the value I mean the contents of the cell.

I will append a matlab file of a dummy structure to the question.

As for the expected output array, I think I specified it as "string array" and "double array".

[Stephen23]

@mahoromax: why do you expect

string(mystruct.somenesting.objecttype.name)

to not throw an error? That comma-separated list likely has far too many inputs for string, nor does string have a syntax with an aribitrary number of input arguments: string converts its first input argument to a string array, whereas you are passing it multiple inputs (as the links in my answer explain).

'As for the expected output array, I think I specified it as "string array" and "double array".'

Have you tried the code in my answer?

[mahoromax]

@Stephen Cobeldick

I was just about to comment your answer, I just wanted to answer these comments first.

As for the error message, it was in return to the first comment I got.

Answer 1

[Stephen23]

string({mystruct.somenesting.objecttype.name})
cat(1,mystruct.somenesting.somethingelse.size)
%   ^ change this to suit the sizes of your data

Read these:

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

[mahoromax]

I think these are the only ways, since I misunderstood that I wanted to not only rebuilt but change the class of my entries.

Your code works, I just thought before there was a way without feeding it into a function (like string()).

Thx for the useful links, the documentation is soo big, but from the entry 'array' I did not find my way to those. I'm still going through them.

[Stephen23]

"Your code works"

I am glad! You can show your appreciation by accepting my answer.

[mahoromax]

I will, I just didnt want to immediately, in case I would find closely related questions.

The impatience XD

[Stephen23]

"I just didnt want to immediately, in case I would find closely related questions."

You are welcome to take your time, and I fully support looking for other/better solutions. It is unfortunately common that some people just disappear as soon as they get a solution :(

I also recommend reading the string documentation carefully, and the links in my answer.