The |structfun| function only works on scalar struct arrays, iterating over the fields of that scalar struct. While you _could_ use |arrayfun|, it may be easier to understand (and perform just as well) if you use a |for| loop. I know people have said "Don't use |for| loops in MATLAB, they're slow." While that may have been true in the past (and you can still write a |for| loop so it is slow in current MATLAB) the performance of |for| loops have increased significantly with the improvements we have made to MATLAB over the years. Besides a |for| loop over 8 elements of a struct array calling |size| is highly unlikely, in my experience, to be the bottleneck in your code.

fnames = fieldnames(data1); temp = cellfun(@(FN) myFunction2(data1.(FN), data2.(FN)), fnames, 'uniform', 0); result = cell2struct(temp, fnames, 1); %might need ,2) instead of ,1)

Hi Alec, You can overload the minus function for structures and then return a structure from it. Implement the function below and save it in a seperate file function C = minus(A,B) C = cellfun(@minus,struct2cell(A),struct2cell(B),'UniformOutput',false); %# Apply plus cell-wise C = cell2struct(C,fieldnames(A)); end A.a = zeros(10, 10, 10) + 1; % 3d all 1s A.b = zeros(10, 10, 10) + 2; % 3d all 2s A.c = zeros(5, 5) + 3; % 2d all 3s B.a = zeros(10, 10, 10) + 1; % 3d all 1s B.b = zeros(10, 10, 10) + 1; % 3d all 1s B.c = zeros(5, 5) + 1; % 2d all 1s. C = A - B %should give you the expected result Thanks, Nikhil

For the impatient reader, the structfun solution is at the bottom of my answer :-) But I would first ask myself...

What's wrong with using a loop? The following example shows how it can be done:

%# An example structure
S.a = 2;
S.b = 3;

%# An example function
MyFunc = @(x) (x^2);

%# Retrieve the structure field names
Names = fieldnames(S);

%# Loop over the field-names and apply the function to each field
for n = 1:length(Names)
    S.(Names{n}) = MyFunc(S.(Names{n}));
end

Matlab functions such as arrayfun and cellfun typically are slower than an explicit loop. I'm guessing structfun probably suffers from the same problem, so why bother?

However, if you insist on using structfun it can be done as follows (I made the example a little more complicated just to emphasize the generality):

%# structfun solution
S.a = [2 4];
S.b = 3;
MyFunc = @(x) (x.^2);
S = structfun(MyFunc, S, 'UniformOutput', 0);

Single line (work for fields with struct NOT objects of class, struct is NOT some sort of class) s.s1.P = (1:20).'; % For simplicity I have assigned dummy values to the "P "s. s.s2.P = (1:20).'; s.s3.P = (1:20).'; sum([cat(1,struct('sx',struct2cell(s)).sx).P],2)

Not entirely sure what you're asking, structfun applies the same function to each field of a scalar structure. It doesn't look like it's what you're after at all. If you're asking how to get the value of a particular field having its name stored as text, yes this can be done easily fname = 'value1'; S.(fname).x Hopefully, your example is for illustration and you're not using numbered variables and numbered field names. Numbered anything is a flawed design and you should replace that with proper indexing: S(1).value(1).x = 1 S(1).value(2).x = 10; S(1).value(3).x = 17; S(2).value(1).x = 12; S(2).value(2).x = 11; S(2).value(3).x = 13; S(3).value(1).x = 142; S(3).value(2).x = 11; S(3).value(3).x = 113; which completely removes the need to generate field names as strings.

You can do this using an anonymous function that calls myfun with the two additional arguments:

cellfun(@(x) myfun(x,const1,const2), cellarray)

structfun(@(fld) reshape(fld, 50, 1), yourstruct) or structun(@(fld) fld(:), yourstruct)