problem in assigning elements

hi, i'm developing a program to measure pupil diameter changes due to a light stimulus.

this is a part of my mfile

clear

video=input('insert video:');

v=aviread(video);

info=aviinfo(video);

n=info.NumFrames;

w=info.Width;

h=info.Height;

t=info.FramesPerSecond;

for a=1:n

p=v(a).cdata<19000;

p1=bwlabel(p);

stats(a) = regionprops(p1,'EquivDiameter');    

end

my program works in this way: 1.acquire video 2.read the video frames 3.locate and calculate the pupil diameter(using the regionprops function)

but the problem is, sometimes a frame can yield more than one diameter value, which return error at the command "stats(a) = regionprops(p1,'EquivDiameter');"

here is the error message:

??? In an assignment A(:) = B, the number of elements in A and B must be the same.

Error in ==> pupil at 15 stats(a) = regionprops(p1,'EquivDiameter');

what i interpret from this error line is, my "stats(a)" variable can only contain 1 value of the "regionprops(p1,'EquivDiameter');" variable

What should i do to make my "stats(a)" variable able to contain more than 1 value from my "regionprops(p1,'EquivDiameter');" variable

Can anyone give me a clue / solution regarding this problem?

Answer 1

[Sean de Wolski]

Define stats as a cell array

stats = cell(n,1);
for ii = 1:n
 %do stuff
 stats{ii} = regionprops(stuff)
end