create a matrix with numbers from vector

i have a vector as

v = [ 1 1 1 2 2 2 3 3 4]

i wanted to create a new matrix as

M = [ 
1 1 1 0 0 0 0 0 0; 
0 0 0 1 1 1 0 0 0;
0 0 0 0 0 0 1 1 0;
0 0 0 0 0 0 0 0 1];

how to do it?

Answer 1

[madhan ravi]

v = [1 1 1 2 2 2 3 3 4];
u=unique(v);
R=arrayfun(@(x)v==u(x),1:numel(u),'un',0);
M=+vertcat(R{:})

Gives:

M =

     1     1     1     0     0     0     0     0     0
     0     0     0     1     1     1     0     0     0
     0     0     0     0     0     0     1     1     0
     0     0     0     0     0     0     0     0     1

Answer 2

[madhan ravi]

Simpler:

M = +(v==unique(v).')

[Stephen23]

+1 very tidy. I like that.

[madhan ravi]

Thank you!

Answer 3

[KSSV]

N = zeros(3,3,3) ;
for i = 1:3
    N(i,:,i) = 1 ;
end

M = reshape(N,3,[])

[KSSV]

Give Example....by the way what is use of v here?

[KSSV]

v = [ 1 1 1 2 2 2 3 3 4] ;
v = reshape(v,[],3)' ;

N = zeros(3,3,3) ;
for i = 1:3
    N(i,:,i) = v(i,:) ;
end

M = reshape(N,3,[])