getfield to get values from an entire struct array?

I have an array of objects of type Peak. Given the name of a field (I will be using several in turn), I would like to get the value of that field for every object in the array, resulting in a vector of double. Is there any way to ask getfield to do that, without resorting to a for loop? Or is there some related function that would do the job for me?

[Stephen23]

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

Answer 1

[Bruno Luong]

Create 1 x 3 struct array with field named 'afield'

s = struct('afield', {11 12 13})

s = 1x3 struct array with fields:
    afield

s(1)

ans = struct with fields:
    afield: 11

s(2)

ans = struct with fields:
    afield: 12

s(3)

ans = struct with fields:
    afield: 13

% Here is the command that might be usefule for you

A = cat(2, s.afield)

A = 1x3

11 12 13

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[Ken]

Yes, but not quite. I need to reference the field name as a quoted string, because the same code will be applied to several different fields, as the user selects which one to graph.

[Bruno Luong]

Take a look at dynamic fieldname

s = struct('afield', {11 12 13});

fieldname = "afield"

fieldname = "afield"

A = cat(2, s.(fieldname))

A = 1×3

11 12 13

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[Ken]

Well I'll be! That is some WEIRD syntax! But it fits my need perfectly. Thank you!