How to access struct member via a string
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Danny
el 5 de Oct. de 2023
Editada: Bruno Luong
el 6 de Oct. de 2023
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 comentario
Stephen23
el 5 de Oct. de 2023
Editada: Stephen23
el 5 de Oct. de 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
el 5 de Oct. de 2023
Editada: Matt J
el 5 de Oct. de 2023
Here is something simiilar:
airplane.cockpit.controls.throttle = 'forward';
s={'cockpit','controls'};
getfield(airplane,s{:})
2 comentarios
Fangjun Jiang
el 5 de Oct. de 2023
airplane.cockpit.controls.throttle = 'forward';
s = "('cockpit').('controls')";
pth=extractBetween(s,"'","'");
getfield(airplane,pth{:})
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Bruno Luong
el 5 de Oct. de 2023
Editada: Bruno Luong
el 6 de Oct. de 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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