getting data from structure

Hi!

I have a structure set up like so:

S(1).speed = [x1 y1 z1];

S(2).speed = [x2 y2 z2];

S(3).speed = [x3 y3 z3];

and so on...

for every entry, the speed data is separated into x, y, and z axis in that order.

how can i, for example, get a vector containing only the speed in the x axis of all the entries? (the first object in every entry)

Answer 1

[David Hill]

T=struct2table(S);
out=T.speed(:,1);

Answer 2

[Fangjun Jiang]

temp=[S.speed];
out=temp(1:3:end)
% or get all three speeds
Speed=reshape([S.speed],3,[])

Answer 3

[Geoff Hayes]

Lichay - you could try something like

speedX = arrayfun(@(k)S(k).speed(1), 1:length(S))

where we use arrayfun to iterate over each element of S and extract the speed in x.