How to access struct member via a string
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Let's say I create a struct via the following:
airplane.cockpit.controls.throttle = 'forward'
I can access those fields like this:
airplane.('cockpit').('controls')
Is it possible to use these semantics but with a string representation? I've tried this:
s = "('cockpit').('controls')"
airplane.(s)
Reason for asking is that I have a configuration file that use the same structure notation to "drill" down into the structure. I'd like to be able to read that configuration file to access certain members of the struct
1 commentaire
Stephen23
le 5 Oct 2023
Modifié(e) : Stephen23
le 5 Oct 2023
"Is it possible to use these semantics but with a string representation?"
Not easily. But you can easily use SPLIT and GETFIELD.
An explanation of why your approach does not work: https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them#answer_966455
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Matt J
le 5 Oct 2023
Modifié(e) : Matt J
le 5 Oct 2023
Here is something simiilar:
airplane.cockpit.controls.throttle = 'forward';
s={'cockpit','controls'};
getfield(airplane,s{:})
2 commentaires
Fangjun Jiang
le 5 Oct 2023
airplane.cockpit.controls.throttle = 'forward';
s = "('cockpit').('controls')";
pth=extractBetween(s,"'","'");
getfield(airplane,pth{:})
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Bruno Luong
le 5 Oct 2023
Modifié(e) : Bruno Luong
le 6 Oct 2023
I made this for my own use. It is not a dot syntax, just the functional form.
The constraint is that accessing nested subfield(s) should be scalar.
Assignment automatically creates the intermediates nested structures if they do not exist.
Error handling when retreive if the intermediate/final nested structures do not exist.
airplane = struct()
airplane = rsetfield(airplane, 'cockpit.controls.throttle' , 'forward')
airplane.cockpit.controls.throttle
[value success] = rgetfield(airplane, 'cockpit.controls.throttle')
[value success] = rgetfield(airplane, 'cockpit.controls.alarm')
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