finding index to a vector in structure

Question

James McDaniel 2015-10-1

评论： Jos (10584) 2015-10-1

Consider the following example:

f = struct
f(1).x = 5;
f(2).x = 1:10;
f(3).x = 1;
f(4).x = 2;

I wish to find an automated way of finding which element of the field x is a vector. In the example above, the answer is element 2. Thank you!

Answer 1

the cyclist 2015-10-1

I could not figure out a vectorize way to do this, but perhaps this loop is good enough:

n = size(f,2);
isVectorF = false(1,n);
for nv = 1:n,
  isVectorF(nv) = not(isscalar(f(nv).x));
end

isVectorF is a logical with 0 = scalar and 1 = vector.

Jos (10584) 2015-10-1

isVectorF = arrayfun(@(k) isvector(f(k).x) && numel(f(k).x)>1 ,1:numel(f))