Sounds like you have something like: b = dir('C:\Windows\'); b(1) names = fieldnames(b(1)); for i = 1:numel(names) value{i} = getfield(b(1),names{i}) end

A_cell = struct2cell(A); D = A_cell{3} Keep in mind that the order of the fields of structs is not necessarily constant: A.B = 1; A.C = 2; A.D = 3; B.B = 1; B.D = 3; B.C = 2; isequal(A, B) % >> TRUE!

You can access a structure dynamically with s.(fname) where fname is char variable. Note the ( ) around fname.

An example will clarify:

% Example structure
s.A = 10;
s.B = 20;

% Retrieve fieldnames
fnames = fieldnames(s);

% Loop with numeric index
for ii = 1:numel(fnames)
    s.(fnames{ii})
end

% ...or loop by fieldname directly
for f = fnames'
    s.(f{:})
end

Try this:

test.A(strcmp({test.A.Name}, 'Eva')).Data

Basically if you call test.A.Name it will return a comma separated list of all the names. So by putting {} around that we concatenate all those into a cell matrix. We can then use strcmp to find the indices that match the name you're after. Note that if your names can be repeated then this will return a comma separated list over all so you might want to put the curly braces around the entire expression in that case.

You just need to use parentheses: S.(fieldname)

Try dynamic field reference where you put a string in the parenthesis as seen on the line defining stuff.

S = struct('A', [1 2], 'B',[3 4 5]); 
SNames = fieldnames(S); 
for loopIndex = 1:numel(SNames) 
    stuff = S.(SNames{loopIndex})
end 

I concur with Steve and Adam. Use cells. This syntax is right for people in other situations though!

You have to do this instead:

a(1).a1

The reason why is because the code you use to create your structure actually creates a 3-element structure array where the first array element contains a1: 1 and a2: 4, the second array element contains a1: 2 and a2: 5, and the third array element contains a1: 3 and a2: 6.

When you use curly braces {} in a call to STRUCT like you did, MATLAB assumes you are wanting to create a structure array in which you distribute the contents of the cells across the structure array elements. If you instead want to create a single 1-by-1 structure element where the fields contain cell arrays, you have to add an additional set of curly braces enclosing your cell arrays, like so:

a = struct('a1',{{1,2,3}},'a2',{{4,5,6}});

Then your original a.a1{1} will work.

EDIT:

If you create your structure using numeric arrays instead of cell arrays, like so:

A = struct('a1',[1 2 3],'a2',[4 5 6]);

Then you can access the value of 1 as follows:

A.a1(1)

For further information about working with structures in MATLAB, check out this documentation page.

I don't think people would really recommend that approach, but here is one way to solve it using the hated eval() function: method1.mean = 30; method2.mean = 40; method3.mean = 50; method4.mean = 60; method5.mean = 70; % Whatever.... structNames = {'method1','method2','method3'}; % List of structs we want to use now. thisSum = 0; for m = 1:length(structNames) commandString = sprintf('%s.mean', structNames{m}) thisMean = eval(commandString) thisSum = thisSum + thisMean end meanSum = thisSum / length(structNames)

If you don't know the field names a priori, you can use fieldnames to get them, then access them using the returned values:

names = fieldnames(s);
vec1 = s.(names{1});
vec2 = s.(names{2});

Alternatively, you can ignore them altogether and just place the structure field contents in a cell array using struct2cell:

vecs = struct2cell(s);
vec1 = vecs{1};
vec2 = vecs{2};