distance

Hi, I'm trying to find middle distance. We did it this way

   c1=handles.centroids(:,1);
   c2=handles.centroids(:,2);
   d1=sqrt(((xi(:,1)-c1))^2+(yi(:,1)-c2)^2);
   d11=sqrt(((xi(:,2)-c1))^2+(yi(:,2)-c2)^2);
   vz1=(d1+d11)/2;

   str = ['strední vzdalenost v prvním okně je ', num2str(d1), ' pixelu.'];
  disp (str);

but my voice is a mistake vcem Does anybody know the problem?

??? Error using ==> mpower
Inputs must be a scalar and a square matrix.

Thank you very much

Answer 1

[Andrei Bobrov]

use .^

d1=sqrt(((xi(:,1)-c1))^2+(yi(:,1)-c2)^2); 
d11=sqrt(((xi(:,2)-c1)).^2+(yi(:,2)-c2).^2);

on comment

d = sqrt((xi-c1).^2+(yi-c2).^2);
vz1 = mean(d);

[Adam]

after treatment system reports this error:

Attempted to access xi(:,2); index out of bounds because

size(xi)=[2,1].

[Jan]

@Adam: The error message is clear: You try to access a not existing element of the array xi. Because you did not explain or show how xi is created, it is impossible to give any advice.

[Adam]

ginput create using the values xi yi, which is also at the function as the rows to calculate the distance.

hold on

n=0;

[xi,yi,but] = ginput(2);

% plot(xi,yi,'g*');

n = n+1;

x(:,n) = xi;

y(:,n) = yi;

plot(xi,yi,'r*');

%xy(:,n) = [xi;yi];

hold off

[Adam]

Well here is the complete code as I realized. When inserting one point so it works, for more no:

file_name ='bw.bmp';

BW = imread(file_name);

imshow (BW)

s3 = regionprops(BW, 'centroid');

centroids3 = cat(1, s3.Centroid);

hold on

plot(centroids3(:,1), centroids3(:,2), 'r*')

hold off

hold on

n=0;

[a,b,but] = ginput(2);

n = n+1;

x(:,n) = a;

y(:,n) = b;

plot(a,b,'r*');

hold off

c1=centroids3(:,1);

c2=centroids3(:,2);

d1=sqrt(((a-c1)).^2+(b-c2).^2);

d11=sqrt(((a-c1))^2+(b-c2).^2);

vz1=(d1+d11)/2;

str = ['strední vzdalenost v prvním okně je ', num2str(vz1), ' pixelu.'];

disp (str);

can be downloaded from the link picture:

http://www.ulozto.cz/xAEvHHw/bw-bmp

[Adam]

I had the problem resolved but it is not very elegant solution ... I'll happy with any help.

thank you