How to draw a line on a logical matrix?

Hi,

Assume a blank matrix:

m=[0 0 0 0 0
   0 0 0 0 0
   0 0 0 0 0
   0 0 0 0 0
   0 0 0 0 0]

I want to draw a line between a=[1 1], b=[5 5], and returned m like this:

m = [1 0 0 0 0
     0 1 0 0 0
     0 0 1 0 0
     0 0 0 1 0
     0 0 0 0 1]

Answer 1

[Andrei Bobrov]

diag(5)

or

z = zeros(6.,7);
a=[2 1];
b=[4 7];

xy = [a; b];
t = diff(xy);
t0 = t(:,1)./t(:,2);
y = @(x)(x - a(2))*t0 + a(1);
x1 = (1:size(z,2))';
y1 = round(y(x1));
z(size(z,1)*(x1 - 1) + y1) = 1

or use strel from Image Processing Toolbox

 z = zeros(6.,7);
 a=[2 1];
 b=[4 7]; 
 t = diff([a; b]);
 S = strel('line',sqrt(sum(t.^2)),atand(t(1)/-t(2)));

[John Wray]

Hi,

thanks for your answer, I mean not to create a diag matrix, the two points can be any value,.